Add option to quote pattern

[lukenels]

To make it easy to to search for fixed pattern files, consider adding a flag such as -q or --quote to interpret the pattern as a literal string as opposed to a regex.

This way commands like fd --quote 'test.c' won't interpret the . as a regex wildcard.

[sharkdp]

I think this is very similar to (or would be possible with) #97?

[sharkdp]

@lukenels This is now supported via --fixed-strings/-F.

[lukenels]

Thanks @sharkdp !