Great! Any help is greatly appreciated
CORE-880 would be a good one to start with. I think the best thing to do is if they put --logLevel or some other unexpected param after the command, it outputs an “unexpected command parameter X” and the help documentation, perhaps with a sentence or two explaining that parameters after the command apply to the command, whereas parameters before the command apply to liquibase setup.
Maven and Git are not to bad to get used to. I actually don’t use maven much myself, I use intellij and have the project configuration committed to git so you just have to open the project and it compiles with the normal intellij compile.
If you use a different editor, it may be easiest to install maven (simply download from apache and unzip, then run mvn package from the root of the liquibase source tree.
Git is also relatively straightforward as well. http://learn.github.com/p/normal.html gives a starting tutorial, and you can find many others on the web. Many IDEs have built-in support for git, so it acts much like SVN, but with an extra “push” command that pushes the changes to the remote repository rather than just your local repository. You can either fork the liquibase github repository, or send patches. Whichever you prefer.
Let me know what questions you have.