Make all mathbars add up right

We have been grappling with data integrity problems. The primary reason
is that there are two factors that are included on one half of the
equation, but not the other:

1. Unpaid bills are counted as an "Expenditure" but do not subtract from
   "Cash on Hand"
2. Candidates can report "Miscellaneous Adjustments" which are things
   like interest, selling things for fair market value, or transfers from
   another committee by the name name.

These are accounted for in two ways:

1. Unpaid bills are subtracted from "Cash on Hand" to produce a new
   figure "Available Balance". This number more-accurately reflects a
   campaign's fiscal status and, if the candidate accrues too many
   unpaid bills, will be negative. I think a negative number reflects
   properly on the candidate's situation.
2. "Miscellaneous Adjustments" are all positive, and as such are
   income, so they are added to "Contributions". This isn't completely
   clean, but the amount of these are negligible.

This adds a bin/test_amounts script which performs the math in the
mathbar to see if it checks out.
Merge pull request #252 from tdooner/master

Make all mathbars add up right
Tighten up mayoral table candidates with no data
Merge pull request #253 from tdooner/master

Tighten up mayoral table candidates with no data
Merge pull request #254 from vbrown608/master

Integrate Ian's chart with new data format. Add a legend and title.
Increase number of whales to 20 #249
Remove candidates self-contributions from inside Oakland
Merge pull request #258 from mikeubell/Oakland

Remove self-contributions from % from Oakland
Use local bootstrap + font awesome
Include assets correctly
Add local copy of FontAwesome
(Temporarily?) Remove CfA logo

See #264
Add Williams to the funded candidates.
Merge pull request #268 from mikeubell/master

Add Williams to the funded candidates.
Fix N+1 Query

This was causing pages with lots of people on it (like the "Retired"
page) to take ~10s to render. Yoinks!
Remove date from aggregated contributions.
Make it clear that its the $$ from inside oakland.
Chagnge Williams short name so he matches his conritbutions.
Merge pull request #269 from mikeubell/master

Remove date from aggregated contributions.
Update READMEs to be a bit more accurate