Add `--newline=[LF|CRLF|native|preserve]` option to `pip-compile`#1652

ssbarnea merged 4 commits intojazzband:masterjazzband/pip-tools:masterfrom

AndydeCleyre:feature/linesep-textiowrapperAndydeCleyre/pip-tools:feature/linesep-textiowrapperCopy head branch name to clipboard