Add support for CRLF line endings in filters

[kvonbredow]

In files created in windows, the CRLF line endings in filters cause jq to crash with an "unexpected INVALID_CHARACTER" syntax error. Since this should just be treated as any other whitespace character to aid in Windows support, I modified the lexer to ignore \r whitespace in filters.

resolves #1219

[coveralls]

Coverage decreased (-0.02%) to 84.947% when pulling 5e6b68b on kvonbredow:CRLF_support into 90bc29c on stedolan:master.

[itchyny]

This issue has been resolved by #2942.

[emanuele6]

No, #2942 did not add \r as a whitespace character, it just made it so \r in a comment does not end the comment, and trigger an INVALID_CHARACTER error for CR.
If you have a \r character in your script, the code will still not compile because \r is invalid; but now \r is at least allowed in comments.

[emanuele6]

Anyhow, this patch probably has conflicts, and extra code would be needed to support # \<cr><lf> comment continuations. So we can keep it closed, I guess.

[itchyny]

Oops, thanks for comment. That sounds a halfway support, so I'd like to see full support CRLF newlines.