add issue template.

.github/ISSUE_TEMPLATE/bug_report.md

@@ -0,0 +1,22 @@
+---
+name: Bug report
+about: Create a report to help us improve
+title: "[bug]"
+labels: ''
+assignees: ''
+
+---
+
+**Describe the bug**
+
+**To Reproduce**
+
+**Expected behavior**
+
+**Platform information**
+
+* **Flutter version**: <!--  flutter doctor -v -->
+* **Plugin version**:
+* **Flutter target OS**: <!--  Android/iOS/Windows/Mac/Web [real device/simulator] -->
+* **Flutter target OS version**:
+* **Flutter console log**: <!-- optional -->

.github/ISSUE_TEMPLATE/custom.md

@@ -0,0 +1,10 @@
+---
+name: Custom issue template
+about: Describe this issue template's purpose here.
+title: ''
+labels: ''
+assignees: ''
+
+---
+
+

.github/ISSUE_TEMPLATE/feature_request.md

@@ -0,0 +1,16 @@
+---
+name: Feature request
+about: Suggest an idea for this project
+title: "[feature]"
+labels: ''
+assignees: ''
+
+---
+
+**Is your feature request related to a problem? Please describe.**
+
+**Describe the solution you'd like**
+
+**Describe alternatives you've considered**
+
+**Additional context**