Added issue templates for different issues

- Added feature request template
- Added proposal template
- Added question template

Signed-off-by: Nisha K <nishak@vmware.com>

.github/ISSUE_TEMPLATE/feature.md

@@ -0,0 +1,17 @@
+---
+name: Feature Request
+about: Request a Feature
+
+---
+
+**Describe the Feature**
+A clear and concise description of what you would like Tern to do for you.
+
+**Use Cases**
+Describe the use case(s) where this feature would be helpful.
+
+**Implementation Changes**
+Describe what changes you think would need to happen to the code to implement this feature
+```
+pseudocode or python code is fine here
+```

.github/ISSUE_TEMPLATE/proposal.md

@@ -0,0 +1,14 @@
+---
+name: Proposal
+about: Propose a change to the project. This covers changes to docs, file organization or CI/CD.
+
+---
+
+**Problem Statement**
+Describe the problem you are facing with the project.
+
+**Describe the Proposal**
+Describe the change you would like to see in the project.
+
+**Steps to Implement Proposal**
+List steps required to implement the change you would like to see.

.github/ISSUE_TEMPLATE/question.md

@@ -0,0 +1,10 @@
+---
+name: Question
+about: Ask a question about the project
+
+---
+
+**Please read the Code of Conduct before you proceed**
+[Code of Conduct](/CODE_OF_CONDUCT.md)
+
+**Ask your question here**