Added a addon icon which can toggle the styles

Now the single and the grid view of the gitlab diff page is styled properly

Removed line count functionality to another plugin

watch/observe url for changes and rerun the calculation

Bugfixes like added jQuery minified slim version and waiting for the document to be loaded via manifest.json

Update for calculating the line changes on a merge requests in gitlab. Calculates added and removed lines on scroll for each directory. Pretty useful if you want to know which directory contains how many changes and to calculate if your big merge requests overall removes or adds more code to the repo.