Replace Treetop parser with a Ragel based parser
Merge remote-tracking branch 'origin/410-no-header-charset' into nmaster
Merge remote-tracking branch 'origin/undefined_conversion_workaround' into nmaster

Conflicts:
	lib/mail/fields/unstructured_field.rb
Merge remote-tracking branch 'origin/497-dont-reorder-parsed' into nmaster
Merge remote-tracking branch 'origin/split-on-crlfcrlf' into nmaster
Merge branch 'lazier-fields2' into nmaster

Conflicts:
	lib/mail/header.rb
Merge branch 'bpot/pure_ruby_ragel_parser' into nmaster
[HACK] Import rapportive encoding hacks

Conflicts:
	lib/mail/message.rb
[HACK] Allow writing to decoded/raw_source
[HACK] remove call to add_required_fields and header.ready_to_send!

Conflicts:
	lib/mail/message.rb