Merge pull request realm#1792 from realm/jp-refactor-issue-template

Split up issue template in "rule request" and "bug report" sections

.github/ISSUE_TEMPLATE.md

@@ -3,31 +3,45 @@
 - [ ] Updated SwiftLint to the latest version
 - [ ] I searched for [existing GitHub issues](https://github.com/realm/SwiftLint/issues)
 
-### Issue Description
+### Rule Request
 
-(If this is a new rule request, please ignore everything below.)
+If this is a bug report, please ignore this section.
+
+If this is a new rule request, please ignore all sections below this one, format
+this issue's title as `Rule Request: [Rule Name]` and describe:
+
+1. Why should this rule be added? Share links to existing discussion about what
+   the community thinks about this.
+2. Provide several examples of what _would_ and _wouldn't_ trigger violations.
+3. Should the rule be configurable, if so what parameters should be configurable?
+4. Should the rule be opt-in or enabled by default? Why?
+   See [README.md](../README.md#opt-in-rules) for guidelines on when to mark a
+   rule as opt-in.
+
+### Bug Report
 
 ##### Complete output when running SwiftLint, including the stack trace and command used
 
-```
+```bash
 $ swiftlint lint
 ```
 
 ### Environment
 
 * SwiftLint version (run `swiftlint version` to be sure)?
-* Installation method used (Homebrew, CocoaPods, building the source, etc)?
+* Installation method used (Homebrew, CocoaPods, building from source, etc)?
 * Paste your configuration file:
 
 ```yml
-included:
-  - you should change this
+# insert yaml contents here
 ```
 
 * Are you using [nested configurations](https://github.com/realm/SwiftLint#nested-configurations)?
+  If so, paste their relative paths and respective contents.
 * Which Xcode version are you using (check `xcode-select -p`)?
-* Do you have a sample example that shows the issue? You can run `echo "[string here]" | swiftlint lint --no-cache --use-stdin --enable-all-rules` to quickly test if your example is really demonstrating the issue. 
-If your example is a more complex one, you can use `swiftlint lint --path [file here] --no-cache --enable-all-rules`.
+* Do you have a sample that shows the issue? Run `echo "[string here]" | swiftlint lint --no-cache --use-stdin --enable-all-rules`
+  to quickly test if your example is really demonstrating the issue. If your example is more
+  complex, you can use `swiftlint lint --path [file here] --no-cache --enable-all-rules`.
 
 ```swift
 // This triggers a violation:

README.md

@@ -206,16 +206,18 @@ Over 75 rules are included in SwiftLint and the Swift community (that's you!)
 continues to contribute more over time.
 [Pull requests](CONTRIBUTING.md) are encouraged.
 
-You can find an updated list of rules and more information about them 
+You can find an updated list of rules and more information about them
 in [Rules.md](Rules.md).
 
 You can also check [Source/SwiftLintFramework/Rules](Source/SwiftLintFramework/Rules)
 directory to see their implementation.
 
+### Opt-In Rules
+
 `opt_in_rules` are disabled by default (i.e., you have to explicitly enable them
 in your configuration file).
 
-Guidelines on when to implement a rule as opt-in:
+Guidelines on when to mark a rule as opt-in:
 
 * A rule that can have many false positives (e.g. `empty_count`)
 * A rule that is too slow