added reqs
Merge branch 'master' of github.com:OpenSourcePolicyCenter/Tax-Calculator
refactor in StdDed
Merge branch 'master' of github.com:OpenSourcePolicyCenter/Tax-Calculator into stdded

Conflicts:
	taxcalc/calculate.py
pass posagi as function argument
Merge pull request #66 from talumbau/fix_posagi

pass posagi as function argument
Merge pull request #64 from talumbau/stdded

Refactor in Std_ded
got latest code from master
refactored and renamed error checker class
removed error checker functionality for now
simplified TaxcalcError class