Small pythonic refactorings

[reinvantveer]

Hi @g-sherman thank you for sharing your plugin builder, it has been a very big help in getting started with QGIS plugin development. I'd like to contribute a few changes and I'll start small. I don't really enjoy huge PRs, so it's basically a few simple proposals to clean up a bit in the Python code:

• I dropped the "Import python stuff" comment, if you don't mind
• single-line the imports (for readability, mostly, got rid of the brackets)
• Python comments take a space after the "#"-sign which I refuse to call a "hashtag" 😛; there's probably more I'm just checking if you agree.
• There was (probably some copy/paste thing) an erroneous docstring for one of the methods