Add missing semicolon

Shush, linter.
Prevent selection-drawing code from calling charCoords with ch: -1
Add Blogger's template editor to real-world uses
[vim keymap] Add Ctrl-a Ctrl-x to increment/decrement numerical tokens
Add test cases for vim key-bindings Ctrl-a/Ctrl-x
[vim keymap] Fully emulate the behavior of Ctrl-a/Ctrl-x
[vim keymap] Allow toggling backtracking in Ctrl-a/Ctrl-x
[vim keymap] Add test for forward searching behavior of Ctrl-a/Ctrl-x