Choose which action(s) you want for each run: --format and/or --lint.
Many different types of files are lint-checkable, but you need Pocketlint
installed (plus ideally, its plugins for the various languages).
Also, added option to control batching of the commands.
The path prefixes listed in .beautify-ignore, in the project root, will not
be cleaned up. C and C++ files everywhere else will be.
Also fixes bugs in the prefix-matching code, and makes the matching a little
bit more powerful: the prefix can now extend down into the directory tree.
