Remove vimrc_after operator match/highlighting.

Add:
	vimrc_after, vim/ftpackage/curly_bracket.vim
		-The recently implemented global syntax matches and highlighting
		for common operator symbols (eg, `+`, `*`, `%`, etc.) fails,
		because some must be declared in a specific order with respect
		to other language-specific matches to prevent overrides.
		-Remove their declarations from both files.
Refactor vimrc, minor edits to DoxygenUtility.

Add:
	vimrc
		-Move certain functions, like `GitBranchName()`, used only in
		other given functions (`StatusLine()`, in this case), from
		global scope into the parent function's local scope.

	vim/scripts/DoxygenUtility/(autoload, plugin)/DoxygenUtility.vim
		-Fix bug that inserted only the first character of an argument
		name into a function-like macro comment.