Adds database update when selecting an estimate

Clicking on an estimation card adds the estimate to the requirement and
updates the database.
Authors: dbeckwith, quan1992
Adds user field to requirement voting

Used to see if the user has already voted for the current requirement.
Still no way of telling what the current user is though...
Authors: dbeckwith, quan1992
Merge pull request #45 from dbeckwith/team9dev

Merge team9dev into feature-store_estimate
Reworks right panel GUI according to Marty

Also adds a feature to the game tree so that it automatically expands a
tree node when you select it, reduces the amount of clicking you need to
do.
Authors: dbeckwith, quan1992
Merge pull request #50 from dbeckwith/feature-store_estimate

Changes some GUI to match Marty's recommendations