Often happened when also toggling file annotations

Adds a better description to blame.line.enabled to be clearer about its behavior
Adds a better description to codeLens.enabled to be clearer about its behavior

undo/redo spawns too many git processes

Refactors diff parsing

Moves annotation messages from formatter to annotations
Moves icons into dark/light folders

Switches to lazy parsing of diff chunks

Turns off whitespace toggling if already 'none'