Clean up implementation of debounce to use debounce rather than throttle

Throttle executes every x miliseconds while debounce waits for user input to finish.
This also fixes the setting that that drives the debounce to be updatable while the editor is running.
Clean up console log and lodash include positioning
Merge pull request #63 from AtomLinter/debounce-modified-event

Add debounce for modified event, reducing the overall quantity of recomputations of linting