Fix incorrect removal of braces in template macros

[dpvc]

This PR fixes a problem with parsing the arguments of a macro with template where braces could be removed incorrectly. For example, with \def\text#1\stop{#1}, if used with \text{a}{b}\stop, you currently will get an error about missing open braces. That is because the parameter #1 will end up containing a}{b rather than {a}{b} as expected.

The solution is to set hasBraces to false when a second braced argument is used. I also changed hasBraces to a boolean rather than a number.

Two new tests are added to check for this issue. There should probably be some more tests for when hasBraces gets unset, for completeness.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 86.68%. Comparing base (351698e) to head (37d7c41).
Report is 4 commits behind head on develop.

Additional details and impacted files

@@             Coverage Diff             @@
##           develop    #1278      +/-   ##
===========================================
- Coverage    86.68%   86.68%   -0.01%     
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  Files          337      337              
  Lines        84105    84102       -3     
  Branches      4750     3125    -1625     
===========================================
- Hits         72909    72906       -3     
- Misses       11173    11196      +23     
+ Partials        23        0      -23     

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[zorkow]

lgtm.