contribution can be updated to paid and cancelled
can update contributions to pending and cancelled, set default amount to 25, and status to pending
Merge pull request #91 from 121watts/contribution-logic

Contribution logic
updates user model relationships
adds totaling method for all contributions of current user
adds totaling method for contributions for current user
Merge branch 'master' of github.com:121watts/the_pivot into contribution-logic
adds totaling method for contributions for current user
Merge branch 'master' of github.com:121watts/the_pivot into front-end
fixed contribution total spec
merges contribution logic
Merge branch 'master' of github.com:121watts/the_pivot into front-end
Changed loan price color and size