Changed MultiReturn to LuaMultiReturn

TypeScriptToLua/TypeScriptToLua#986

Author: lolleko

docs/advanced/language-extensions.md

@@ -16,15 +16,15 @@ TypeScriptToLua provides several extensions to the TypeScript language in the fo
 }
 ```
 
-## MultiReturn Type
+## LuaMultiReturn Type
 
-This language extension allows typing of Lua functions that return multiple values. For example, consider Lua's `string.find`, it returns two indices: the start of the found substring and the end of the found substring. In TypeScript, functions can only return one value so a special type is needed to indicate to tstl there are multiple return values. This is the `MultiReturn<>` type.
+This language extension allows typing of Lua functions that return multiple values. For example, consider Lua's `string.find`, it returns two indices: the start of the found substring and the end of the found substring. In TypeScript, functions can only return one value so a special type is needed to indicate to tstl there are multiple return values. This is the `LuaMultiReturn<>` type.
 
 It allows us to declare `string.find` like this:
 
 ```ts title=stringfind.ts
 declare namespace string {
-  export function find(haystack: string, needle: string): MultiReturn<[number, number]>;
+  export function find(haystack: string, needle: string): LuaMultiReturn<[number, number]>;
 }
 
 const [start, end] = string.find("Hello, world!", "world");
@@ -37,15 +37,15 @@ start, ____end = string.find("Hello, world!", "world")
 ```
 
 :::note
-Prefer MultiReturn over the similar [@tupleReturn annotation](./compiler-annotations.md#tuplereturn). MultiReturn can do anything tupleReturn can, with the added benefit of being able to distinguish between actual tuple tables and multiple return values in the type system.
+Prefer LuaMultiReturn over the similar [@tupleReturn annotation](./compiler-annotations.md#tuplereturn). LuaMultiReturn can do anything tupleReturn can, with the added benefit of being able to distinguish between actual tuple tables and multiple return values in the type system.
 :::
 
 ### \$multi
 
-In order to create a function that returns multiple values it needs to return a `MultiReturn<>` type. This is where the `$multi` function comes in. Calling `$multi` in a return statement will create an instance of the `MultiReturn<>` type:
+In order to create a function that returns multiple values it needs to return a `LuaMultiReturn<>` type. This is where the `$multi` function comes in. Calling `$multi` in a return statement will create an instance of the `LuaMultiReturn<>` type:
 
 ```ts title=multi.ts
-function myFunc(): MultiReturn<[string, number]> {
+function myFunc(): LuaMultiReturn<[string, number]> {
   return $multi("foo", 4);
 }