Release 0.7.3

[MattHJensen]

Please edit the table below adding your significant contributions as they are merged to master.

The highest-numbered pull request included in 0.7.2 was #1082, which was merged into master on 29-Nov-2016.

Significant contributions to Tax-Calculator release 0.7.3

Contributor	PR#	Description
Martin Holmer	#1081	add ability to use an expression to specify a policy parameter
Martin Holmer	#1083	expand scope of JSON reform file to include non-policy parameters
Martin Holmer	#1088	fix capital-gains-reform bug reported by Cody Kallen
Martin Holmer	#1098	add ability to conduct normative expected-utility analysis
Cody Kallen	#1104	add ability to compute MTR with respect to charitable cash contribs
Zach Risher	#1092	provide Pandas 0.19.1 compat by fixing dataframe.to_csv() usage
Zach Risher	#1094	unify environment definition by removing requirements.txt
Matt Jensen	#1109	reorganize current_law_policy.json and add section headers
Cody Kallen	#1084	add dollar limit on itemized deductions
T.J. Alumbaugh	#1111	add testing for Windows with Appveyor

[zrisher]

Zach Risher - #1092 - provide Pandas 0.19.1 compat by fixing dataframe.to_csv() usage
Zach Risher - #1094 - unify environment definition by removing requirements.txt

[MattHJensen]

I am hoping to release 0.7.3 on Monday after #1113 is resolved.

[MattHJensen]

Thanks everyone. Released 0.7.3 https://github.com/open-source-economics/Tax-Calculator/releases/tag/0.7.3

Please let me know if you'd like any changes to the notes.