+ issue templates

.github/ISSUE_TEMPLATE/config.yml

@@ -0,0 +1,9 @@
+blank_issues_enabled: true
+contact_links:
+  - name: Propose a new lint
+    url: https://github.com/dart-lang/linter/issues/new?assignees=&labels=enhancement%2C+lint+request&template=lint-request.md&title=
+    about: Request a new lint rule.
+  - name: Report an issue with a lint
+    url: https://github.com/dart-lang/linter/issues/new?assignees=&labels=&template=issue-report.md&title=
+    about: Create an issue report for an existing lint.
+

.github/ISSUE_TEMPLATE/lint-propoposal.md

@@ -0,0 +1,14 @@
+---
+name: Lint proposal
+about: Propose adding an existing lint rule to a defined rule set.
+title: ''
+labels: type-lint
+assignees: ''
+
+---
+
+**Describe the rule you'd like to see added and to what rule set**
+Include as much detail as you can. 
+
+**Additional context**
+Add any other considerations or context here.