Gersemi

Fixed
- line comments in unknown custom commands are preserved in their original form
- fail-safe for AST mismatch (between before and after reformatting) now properly reports file where the problem occured

Added
- utilize multiple cores if avaiable through `multiprocessing` module
- use `--quiet` to suppress non-error message on stderr
- support for commands from `cmake-modules` section of CMake documentation
- support formatting of custom commands without keyworded arguments
- custom command definitions can be marked now with ` gersemi: ignore` to suppress generating specialized formatter for these commands

Changed
- commands with `PROPERTIES` keyword such as `set_directory_properties` now are formatted in uniform way as other commands with keyworded arguments

Fixed
- idempotence of preserving formatting of unknown custom commands

Fixed
- fixed condition syntax formatting edge-case with opening parenthesis indentation

Fixed
- Missing value for one value keyword no longer leads to stopping formatting of remaining files in the batch

Added
- custom commands formatting when definitions of these commands are provided with `--definitions`
- preserving CRLF style of newlines if formatted file used that style
- `--version`
- performance improvements

Fixed
- bracket argument / bracket comment parsing bugfixes
- removed strict dependency to lark `0.8.0`, now anything from `0.8` but below `0.9` should work

Changed
- formatting of COMMAND keyworded arguments look better when wrapped to line (or multiple lines) instead of listing each constituent of command in separate line