the mode for "Properties files" should be "properties", not "clike"
[vim mode] Fix visual mode downwards movement bug

Previously, if you tried to move further down the document than exist
the cursor would not move down.  This sets selectionEnd.line to be
no greater than the total length of the document.
[rst mode] LaTex/Python inner mode glitches

The were some minor issues w.r.t. where exactly an `stex` or `python`
inner mode starts and where the outer `rst` mode resumes; fixed.
[rst mode] Removed unknown bugs catcher