specify .dir-rtl for rtl CSS so it can be  bidi

If providing both rtl and ltr CSS in one file this needs to be specified.
hide the ell content, not the cell on phones

When the cell is hidden, the header cell can't be so the table
content is all shifted over one cell.

Hiding the content of the cell instead fixes this, though the
best solution is probably to reformat the table completely for
phones and have most of the cells 100% width.
add padding to the default mod_data template layout

I wasn't aware that mod_data added these classes to the default
layout that it generates. It's possible that this might allow
them to be done responsively too. But this starts just by adding
a bit of padding to the table cells.
remove unused exlcude as per https://moodle.org/mod/forum/discuss.php?d=258896#p1126135
Merge pull request #270 from wezley98/excludehtml

remove unused exlcude as per https://moodle.org/mod/forum/discuss.php?d=...
clean renderers with moodle code checker
Pass course summary through formatters for coursebox
Merge pull request #271 from wezley98/codechecker

clean renderers with moodle code checker
Merge pull request #272 from rbayliss/master

Pass course summary through formatters for coursebox