The function `hum/hide-unmatched-lines` uses the function
`mc/cursor-beg`, defined in `mc-mark-more.el`, however the feature is
not required leading to failures in some edge case. Fixes#187
This minor mode when enabled hides all lines where no cursors (and
also hum/lines-to-expand below and above) To make use of this mode
press "C-'" while multiple-cursor-mode is active. You can still
edit lines while you are in mc-hide-unmatched-lines mode. To leave
this mode press "<return>" or "C-g"
