fix tag regexp to match quoted groups correctly

Fixed issue in lexer where the regexp used to match tags would not
correctly interpret quoted sections individually. While this parsing issue
still produced the same expected tag structure later on, the mis-handling
of quoted sections was also subject to a regexp crash if a tag had a large
number of quotes within its quoted sections.

Fixes: #366
Change-Id: I74e0d71ff7f419970711a7cd51adcf1bb90a44c0
3 files changed