- Added recognition for numbers with underscores.
  (More cute Perl syntax...)
- Added _ as non-symbol when trying to recognise
  quoted pairs in cases like "s_identifier".
- Added test notes on ' and :: operators possible
  confusion with quoted pair syntax. ' is okay,
  :: has ambiguous cases but such cases ought to
  be rare. No need to fix unless someone actually
  writes this kind of code...

Changed vs last contribution (not sure about CVS
HEAD because the last time I checked viewCVS the
LexPerl.cxx file looked a little strange...):
- HEREDOC removed test for '\' immediately after <<
- HEREDOC added test for '$' and '@' imm. after <<
  Perl parses these cases as left shift expressions.
- Improve lexing for repetition sequences like 3x3
- Removed unused sooked* variables.
- Clean up ColourTo calls, removed two redundants.
  Removed one or two other bits of redundant code.
- Cut +1400 bytes from object code size by changing
  char Delimiter[256] to a pointer and an allocated
  array; limit all local vars on ColourisePerlDoc()
  to within 8 bits of EBP, so generated code saves 3
  bytes each for most local variable access by using
  8-bit EBP displacements (avoiding 32 bit disps.)
- Revised preferRE behaviour (a full list has been
  prepared in the test case file, with tests.)
- Removed preferRE state consistency problems by
  using explicit backpeeking for all slash chars.
  Little backpeeking is actually needed. Unless the
  Perl code is really bizzare, there shouldn't be
  any performance issues.
- Added extra backtrack testing for {} brace pairs
  to detect hash variables, for better slash state
  interpretation. This also fixes an old SF bug,
  which can be closed.

Priority wrap can wrap first line in document.
Selection margin drawn after wrapping.
Check modification for wrap performed after line heights scrolled because
of line insertion or deletion.

- fixed * multiply, ** exponent op conflict with symbol
table op
- added <<= left shift assignment case
- added x and x= repetition operator classification
- added :: module operator recognition for variables
- separated SCE_PL_WORD|SCE_PL_IDENTIFIER and
SCE_PL_NUMBER lexing
- added backtracking for multi-line ",' and ` strings
- added number lexing with basic hex,bin,octal,float
recognition
- added Unicode vector string lexing
- added special cases for $`` and @+
- removed duplicate SCE_PL_DEFAULT section by
restarting lexing
  (for consistent multi-char or special starting cases)