update submodules
fix bug in image dimensions in LaTeX
Merge branch 'master' of github.com:fletcher/MultiMarkdown-4
Merge pull request #5 from ceeeeej/master

Update .gitmodules 'greg' URL to https://
update markdown test suite module
version bump 4.2.1
fix typo in README
improve parsing inside table cells
update test suite for CriticMarkup support
update test suite for CriticMarkup support
add <nav>/<main> support; fix error in table cell
change 'gcc' to '71152(CC)'
update greg
improve dollar sign math detection
update test suite
tweak HTML comment detection 'recipe' to less false positives
update submodules
add support for inline footnotes
fix memory leak in last commit
update submodule