Update configuration.md to reflect change in luaTarget values (#31)

* Update configuration.md

* add description of universal configuration option

* Update configuration.md

Author: lostfictions

docs/configuration.md

@@ -16,16 +16,16 @@ To customize transpilation behavior we add a new group of options to the `tsconf
 }
 ```
 
-| Option               | Values                                                               | Description                                                                                                                                                                  |
-| -------------------- | -------------------------------------------------------------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
-| `luaTarget`          | `"JIT"`, `"5.3"`, `"5.2"`, `"5.1"` (default: `"JIT"`)                | Specifies the Lua version you want to generate code for.                                                                                                                     |
-| `noImplicitSelf`     | `true`, `false` (default: `false`)                                   | If true, treats all project files as if they were prefixed with<br />`/** @noSelfInFile **/`.                                                                                |
-| `noHeader`           | `true`, `false` (default: `false`)                                   | Set this to true if you don't want to include our header in the output.                                                                                                      |
-| `luaLibImport`       | `"inline"`, `"require"`, `"always"`, `"none"` (default: `"require"`) | We polyfill certain JavaScript features with Lua functions, this option specifies how these functions are imported into the Lua output.                                      |
-| `sourceMapTraceback` | `true`, `false` (default: `false`)                                   | Overrides Lua's `debug.traceback` to apply sourcemaps to Lua stacktraces. This will make error messages point to your original TypeScript code instead of the generated Lua. |
-| `luaBundle`          | File path (relative to the `tsconfig.json`)                          | Will bundle all output lua files into a single bundle file. Requires **luaBundleEntry** to be set!                                                                           |
-| `luaBundleEntry`     | File path (relative to the `tsconfig.json`)                          | This should be the name/path of the TS file in your project that will serve as entry point to the bundled code.                                                              |
-| `luaPlugins`         | `Array<{ name: string; import?: string }>`                           | List of [TypeScriptToLua plugins](api/plugins.md).                                                                                                                           |
+| Option               | Values                                                                     | Description                                                                                                                                                                  |
+| -------------------- | -------------------------------------------------------------------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
+| `luaTarget`          | `"JIT"`, `"5.3"`, `"5.2"`, `"5.1"`, `"universal"` (default: `"universal"`) | Specifies the Lua version you want to generate code for. Choosing `universal` makes TypeScriptToLua generate code compatible with all supported Lua targets.                 |
+| `noImplicitSelf`     | `true`, `false` (default: `false`)                                         | If true, treats all project files as if they were prefixed with<br />`/** @noSelfInFile **/`.                                                                                |
+| `noHeader`           | `true`, `false` (default: `false`)                                         | Set this to true if you don't want to include our header in the output.                                                                                                      |
+| `luaLibImport`       | `"inline"`, `"require"`, `"always"`, `"none"` (default: `"require"`)       | We polyfill certain JavaScript features with Lua functions, this option specifies how these functions are imported into the Lua output.                                      |
+| `sourceMapTraceback` | `true`, `false` (default: `false`)                                         | Overrides Lua's `debug.traceback` to apply sourcemaps to Lua stacktraces. This will make error messages point to your original TypeScript code instead of the generated Lua. |
+| `luaBundle`          | File path (relative to the `tsconfig.json`)                                | Will bundle all output lua files into a single bundle file. Requires **luaBundleEntry** to be set!                                                                           |
+| `luaBundleEntry`     | File path (relative to the `tsconfig.json`)                                | This should be the name/path of the TS file in your project that will serve as entry point to the bundled code.                                                              |
+| `luaPlugins`         | `Array<{ name: string; import?: string }>`                                 | List of [TypeScriptToLua plugins](api/plugins.md).                                                                                                                           |
 
 ## Standard options