Update to 0.9.20 from https://github.com/SEL-Columbia/pyxform
with new ODK Validate 1.4.3
Add geoshape, geotrace types, update readme.rst, CHANGES.txt
Missed add of geoshape and geotrace question types

First add attempt didn't quite do it.
Merge SEl-Columbia/pyxform' into UW-ICTD/pyxform

* master: (25 commits)
  update to ODK Validate 1.4.3 for ODK Collect v1.4.3 and newer.jar
  add test for search and select function
  test for pulldata function in xlsform
  add ODK Validate.jar development version 1.4.3
  pep8 cleanup
  SurveyCTO added support for intent column to XLSForm and translated ${field name} references inside appearance columns for input, and inside intent columns for group fields, in order to support full range of external-intent support.
  Broadened to allow "required message" as the column name.
  For SurveyCTO's dynamic-select support, resolve field references in image columns so that images can also be resolved from the .csv file.
  For SurveyCTO's dynamic-select support, resolve field references in appearance columns, to support query calls in there.
  Testing a unicode CSV can be converted to dict in xls2json_backends. addresses #111
  version bump to 0.9.20
  use style column to defined body class attribute
  Moved aliases to an 'aliases.py' file
  version bump to 0.9.19
  pep8 cleanup
  pep8 cleanup
  changed style attribute to class attribute
  Adds --json flag to output error messages in JSON format
  remove comments when parsing xform
  pep8 cleanup
  ...

Conflicts:
	CHANGES.txt
	pyxform/xls2json.py
example_xls for geoshape and geotrace, closes #114