Removes a workaround that would break moving a range to the current line because it would always move the caret to the start of the range. Now positions the caret to the start of the selection if there is one. This also means we can remove the SAVE_VISUAL flag from JoinLinesCommand
Fixes VIM-2936
Also fixes a memory leak registering a disposable for each yank, allows config variables to be numbers rather than strings and removes highlights when IdeaVim is disabled
Fixes VIM-2236
Because of some reason, the visual position function from the platform starts to return an incorrect column for offsets with tabs. Maybe this is a correct behaviour for the platform, but for IdeaVim it breaks the calculation of the current caret position.
The visual position for calculating the shift was used since 2003, but there is no specific reason to use it and not the buffer (logical) position. So, since it started to cause issues, it's replaced with the buffer position.
