Changing default final estimate to 0

Changes the default final estimate for requirements to 0

Author: lhunker
Merge remote-tracking branch 'origin/team9dev' into final_estimate
Final estimate field auto-fills mean

The field for setting a final estimate now autofills with the mean for
user convience

Author: lhunker
Merge pull request #89 from dbeckwith/final_estimate

Final estimate