Fix #1691 create ISSUE_TEMPLATE and PULL_REQUEST_TEMPLATE

.github/CONTRIBUTING.md

@@ -0,0 +1,30 @@
+# How to contribute
+
+## You found a bug
+Please [open a new issue](https://github.com/wallabag/wallabag/issues/new).
+
+To fix the bug quickly, we need some infos:
+* your wallabag version (on top of the ./index.php file, and also on config page)
+* your webserver installation :
+  * type of hosting (shared or dedicated)
+  * in case of a dedicated server, the server and OS used
+  * the php version used, eventually `phpinfo()`
+* which storage system you choose at install (SQLite, MySQL/MariaDB or PostgreSQL)
+* any problem on the `wallabag_compatibility_test.php` page
+* any particular details which could be related
+
+
+If relevant :
+* the link you want to save and which causes problem
+* the file you want to import into wallabag, or just an extract
+
+If you have the skills :
+* enable DEBUG mode and look the output at cache/log.txt
+* look for errors into php and server logs
+
+Note : If you have large portions of text, use [Github's Gist service](https://gist.github.com/) or other pastebin-like.
+
+## You want to fix a bug or to add a feature
+Please fork wallabag and work with **the dev branch** only. **Do not work on master branch**.
+
+[Don't forget to read our guidelines](https://github.com/wallabag/wallabag/blob/dev/GUIDELINES.md).