start splitting out parser for streaming decoder

	modified:   lib/Text/ZPL.pm
micro-optimize new _decode_* functions

	modified:   bench/vs_json_pp.pl
	modified:   lib/Text/ZPL.pm
split out _decode_handle_level

	modified:   lib/Text/ZPL.pm
_trim_ functions, minor optimizations

	modified:   lib/Text/ZPL.pm
Merge branch 'stream'

* stream:
  _trim_ functions, minor optimizations
  split out _decode_handle_level
  micro-optimize new _decode_* functions
  start splitting out parser for streaming decoder