Add ISSUE_TEMPLATE for github

.github/ISSUE_TEMPLATE.md

@@ -0,0 +1,53 @@
+If you encounter a bug or you have a support question, please try to fill out some of the information below.
+However, if you think your issue does not need any of it, you may omit it.
+Generally speaking, the information below is meant for helping debugging issues
+but they are no prerequisite for opening issues.
+
+### Subject of the issue
+Describe your issue here.
+
+### Your environment
+* Output of `haskell-language-server --probe-tools` or `haskell-language-server-wrapper --probe-tools`
+  * This command is available since version `>= 0.4.0.0`
+* Which lsp-client do you use
+  * Neovim, emacs, VS Codium, etc...
+* Describe your project (alternative: link to the project)
+  * Include `stack.yaml`
+  * Include `package.yaml`
+  * Include `*.cabal` files
+  * Include `cabal.project`
+* Contents of `hie.yaml`
+
+### Steps to reproduce
+Tell us how to reproduce this issue.
+
+### Expected behaviour
+Tell us what should happen.
+
+### Actual behaviour
+Tell us what happens instead.
+
+### Include debug information
+Execute in the root of your project the command `haskell-language-server --debug .` and paste the logs here:
+
+<details>
+<summary>
+Debug output:
+</summary>
+
+```
+<paste your logs here>
+```
+</details>
+
+Paste the logs from the lsp-client, e.g. for [VS Code](https://github.com/haskell/vscode-haskell#troubleshooting)
+
+<details>
+<summary>
+LSP logs:
+</summary>
+
+```
+<paste your logs here>
+```
+</details>