ADD CONTRIBUTING.md

CONTRIBUTING.md

@@ -0,0 +1,23 @@
+## Structure
+
+1. Every example has to be in its own folder. The name of the folder should
+   tell the reader what the example shows.
+2. Contents of that folder:
+    1. Every example has to have a `Makefile` which contains all the commands
+       necessary to compile the document.
+    2. The main TeX file should have the same name as the folder.
+    3. Every example has to have a `README.md`. For images / graphic examples,
+       this should include the rendered image. For documents, there should be
+       some example text explaining what it is about.
+3. Use spaces for indenting.
+
+
+## Commit messages
+
+1. Separate subject from body with a blank line
+2. Limit the subject line to 50 characters
+3. Capitalize the subject line
+4. Do not end the subject line with a period
+5. Use the imperative mood in the subject line
+6. Wrap the body at 72 characters
+7. Use the body to explain what and why vs. how