The base16 scanner never added any digits to the CharClass it was
supposed to be filling---hence the scanner did a lot of work but was
ultimately a no-op. Fixed.
base16 flex scanner pattern no longer has leading context, so hits start
at pos, not pos+1.
Copied and mildly converted patterns from flex scanners (except for
scan_headers.flex, which is marked "do not use" at the top) to C
strings.
Reduced singleton character classes to characters.
Patterns now constructed from subpatterns.
Print the patterns to stdout.
Fixed problems with several patterns.
Replaced repetitious subpatterns with repetition operators.
Simplified MAC address pattern.
Removed a slew of extraneous parentheses.
Reduced some singleton character classes to literals.
Shortened PC and XPC with ranges. Collapsed some singleton character
classes to literals.
Removed stale FIXMEs.
Simplified MONTH subpattern.
More pattern simplification.
Let liblightgrep handle rendering patterns as UTF-16LE.
Pattern simplification.
Move headers other than config.h after HAVE_LIBLIGHTGREP check, since
they don't need to be read if HAVE_LIBLIGHTGREP is false.
Cleanup.
Combined UTF-8 and UTF-16LE email patterns.