Add instructions how to work on and create patches in WunderTools environment

[aleksijohansson]

In order to create patches one needs to at least do the following specific tasks on the WunderTools environment:

• Make the current folder writable (create custom local command in site.yml that does only that)
• Clone the contrib module for example into the drupal/current/sites/all/modules folder
• Be aware that anything that updates the build (usually the ./build.sh update command wipes all work done in the contrib module that was cloned under the drupal/current folder

[badrange]

This just came to mind: Another option is to clone to module to code/modules/custom while removing it from site.make temporarily. You can even push this to the repo, in a separate branch, for others to work on the same patch. I'm quite sure that your development tools will handle this extra .git folder just fine - not sure about the remote repo

[aleksijohansson]

If that works it would be great, because then the changes would be safe in the project repo, but it would also allow the creation of the actual patch file with git when changes are ready. But this is exactly the reason why I think there should be instructions added to this project to describe what is the best way to do this.