Add comments to macro syntax; conventions for keymap syntax
Regression fixes for "useless style revisions", way to go
Add command "Convert to YAML and Rearrange Syntax Definition"

This will automate switching from e.g. JSON or bad old PList to YAML syntax
defs because you only need to run one command now.

Other changes partially required for this:
- Update "WindowAndTextCommand" to correctly update self.view when called as a
  text command
- Add "ext", "open_new_file" and "rearrange_yaml_syntax_def" parameters to
  "convert_file" command
- Add "save" parameter to "rearrange_yaml_syntax_def" command
- Update docstrings
Match `include: #lol` as a comment, fix $self includes
Prepend default options in Rearrange YAML... command
Fix Highlighting of non-alphanumeric simple completions in completion files
Fix wrong paths for syntax paths in commands

See 937cfafb75e91e043e1b1dc744214bdf4a92787b for the relevant change.
Also see 6508299f8f25fec923e41fd7263ffe5e11c36197 for a very similar commit.
Revamp Raw Snippets language

- More variables
- Better substitution highlighting (including substituting variables)
General small adjustments