Included sheet.json and preview image

Preview is of *current* sheet, not final product. The existence of
sheet.json is not an indication of preparedness to submit to the yaml,
so it has been renamed sheet.json.INCOMPLETE.
Cleaning master

Until this project is ready for final submission, exalted2e.jpg and
sheet.json should stay OUT out the master branch. Updates to them should
be placed in the do-not-pull branch.
Added images

Added images folder so that we don't attempt hotlinking
Massive overhaul

- Updated layout
- Standardized attribute names
- "zero" checkbox now uses attr|max field to reduce number of generated
attributes
- removed many roll buttons breaking the layout
- bio/attr/ability should be complete; still need advantages
Merge pull request #84 from Lithl/master

Exalted 2e Update