Merge branch 'community-issue-templates' into 'master'

First pass for community issue templates

## What does this MR do?

Includes community issue templates for Bugs and Feature Proposals.

In combination with a default Issue description template in the Project settings, we can advise the best places to find help and what is suitable to be posted to the CE issue tracker.

## Are there points in the code the reviewer needs to double check?

Verify that the templates are good

## Why was this MR needed?

To bring uniformity to the issues posted to the CE issue tracker

## What are the relevant issue numbers?

## Screenshots (if relevant)

## Does this MR meet the acceptance criteria?

N/A

See merge request !5954

.gitlab/issue_templates/Bug.md

+### Summary
+
+(Summarize the bug encountered concisely)
+
+### Steps to reproduce
+
+(How one can reproduce the issue - this is very important)
+
+### Expected behavior
+
+(What you should see instead)
+
+### Actual behaviour
+
+(What actually happens)
+
+### Relevant logs and/or screenshots
+
+(Paste any relevant logs - please use code blocks (```) to format console output,
+logs, and code as it's very hard to read otherwise.)
+
+### Output of checks
+
+#### Results of GitLab application Check
+
+(For installations with omnibus-gitlab package run and paste the output of:
+`sudo gitlab-rake gitlab:check SANITIZE=true`)
+
+(For installations from source run and paste the output of:
+`sudo -u git -H bundle exec rake gitlab:check RAILS_ENV=production SANITIZE=true`)
+
+(we will only investigate if the tests are passing)
+
+#### Results of GitLab environment info
+
+(For installations with omnibus-gitlab package run and paste the output of:
+`sudo gitlab-rake gitlab:env:info`)
+
+(For installations from source run and paste the output of:
+`sudo -u git -H bundle exec rake gitlab:env:info RAILS_ENV=production`)
+
+### Possible fixes
+
+(If you can, link to the line of code that might be responsible for the problem)

.gitlab/issue_templates/Feature Proposal.md

+### Description
+
+(Include problem, use cases, benefits, and/or goals)
+
+### Proposal
+
+### Links / references

CONTRIBUTING.md

@@ -129,7 +129,7 @@ request that potentially fixes it.
 
 ### Feature proposals
 
-To create a feature proposal for CE and CI, open an issue on the
+To create a feature proposal for CE, open an issue on the
 [issue tracker of CE][ce-tracker].
 
 For feature proposals for EE, open an issue on the
@@ -144,16 +144,7 @@ code snippet right after your description in a new line: `~"feature proposal"`.
 Please keep feature proposals as small and simple as possible, complex ones
 might be edited to make them small and simple.
 
-You are encouraged to use the template below for feature proposals.
-
-```
-## Description
-Include problem, use cases, benefits, and/or goals
-
-## Proposal
-
-## Links / references
-```
+Please submit Feature Proposals using the ['Feature Proposal' issue template](.gitlab/issue_templates/Feature Proposal.md) provided on the issue tracker.
 
 For changes in the interface, it can be helpful to create a mockup first.
 If you want to create something yourself, consider opening an issue first to
@@ -166,55 +157,11 @@ submitting your own, there's a good chance somebody else had the same issue or
 feature proposal. Show your support with an award emoji and/or join the
 discussion.
 
-Please submit bugs using the following template in the issue description area.
+Please submit bugs using the ['Bug' issue template](.gitlab/issue_templates/Bug.md) provided on the issue tracker.
 The text in the parenthesis is there to help you with what to include. Omit it
 when submitting the actual issue. You can copy-paste it and then edit as you
 see fit.
 
-```
-## Summary
-
-(Summarize your issue in one sentence - what goes wrong, what did you expect to happen)
-
-## Steps to reproduce
-
-(How one can reproduce the issue - this is very important)
-
-## Expected behavior
-
-(What you should see instead)
-
-## Relevant logs and/or screenshots
-
-(Paste any relevant logs - please use code blocks (```) to format console output,
-logs, and code as it's very hard to read otherwise.)
-
-## Output of checks
-
-### Results of GitLab Application Check
-
-(For installations with omnibus-gitlab package run and paste the output of:
-sudo gitlab-rake gitlab:check SANITIZE=true)
-
-(For installations from source run and paste the output of:
-sudo -u git -H bundle exec rake gitlab:check RAILS_ENV=production SANITIZE=true)
-
-(we will only investigate if the tests are passing)
-
-### Results of GitLab Environment Info
-
-(For installations with omnibus-gitlab package run and paste the output of:
-sudo gitlab-rake gitlab:env:info)
-
-(For installations from source run and paste the output of:
-sudo -u git -H bundle exec rake gitlab:env:info RAILS_ENV=production)
-
-## Possible fixes
-
-(If you can, link to the line of code that might be responsible for the problem)
-
-```
-
 ### Issue weight
 
 Issue weight allows us to get an idea of the amount of work required to solve