Add "make format-diff" and "make format" commands that use clang-format to reformat source.
Merge pull request #4204 from abika/master

correct selection after removing rows in playlist
Few style fixes + avoid unneeded copies
Iterate over a copy of the parents container since we are removing elements from the original.
Merge pull request #4209 from paperbagcorner/fix-forloop

Iterate over a copy of the parents container since we are removing elements from the original