Added an attributes file and generalize github templates (#109)

.gitattributes

@@ -0,0 +1,13 @@
+* text=auto
+
+*.css diff=css
+*.html diff=html
+*.md diff=markdown
+*.php diff=php
+
+/.github export-ignore
+/tests export-ignore
+.editorconfig export-ignore
+.gitattributes export-ignore
+.gitignore export-ignore
+phpunit.xml export-ignore

.github/CODE_OF_CONDUCT.md

@@ -0,0 +1,3 @@
+# Code of Conduct
+
+The Leaf Code of Conduct can be found in the [Leaf website](https://leafphp.dev/coc).

.github/CONTRIBUTING.md

@@ -0,0 +1,3 @@
+# Contribution Guide
+
+The Leaf Contribution Guide can be found in the [Leaf website](https://leafphp.dev/community/contributing.html).

.github/PULL_REQUEST_TEMPLATE.md

@@ -0,0 +1,16 @@
+<!--
+	Please only send a pull request to branches which are currently supported: https://leafphp.dev/community/contributing.html#pull-request-guidelines
+
+	Pull requests without a descriptive title, thorough description, or tests will be closed.
+-->
+
+## Description
+
+<!--
+	Describe your changes in detail. In addition, please describe the benefit to end users; the reasons it does not break any existing features; how it makes building web applications easier, etc.
+-->
+
+## Related Issue
+
+<!-- If suggesting a new feature or change, please discuss it in an issue first -->
+<!-- If fixing a bug, there should be an issue describing it with steps to reproduce -->