generated donation, interest, & transaction

the donation process. a donation is created by a donor (or user that's not logged in) and recipients can show interest. A coordinator will create a transaction between a donation and a recipient. basic views and forms.

issue #8 
I think adding longitude and latitude values in addition to the address would be helpful for the coordinator dashboard, since it'll be expensive to make google api calls to find the long/lat for an address every time