Reworked inclusion of scripts and link

Links to jQuery and fixit.js are no longer duplicated when processHTML.js
is run twice. Same goes for link to fixit.css.
Replaced getUniqueID with node-uuid

Added a dependency to package.json and removed the getUniqueID function
Renamed getUniqueID to getTimeStamp
Replaced specific links with config settings

Links to fixit.js and fixit.css should now be configured in config/config.js
Added a "file exists" check
Adding of fixit_toggle and data-fixit-id is conditional

- When run on the same HTML twice, IDs are not regenerated and
buttons are not duplicated.
- Also added some comments.