BUG: @cache_readonly didn't reset if series values changed. Reverting to @property.
TST: Test for total_bounds proprty if values in series change
ENH: Allow geometry property to be set.

* Allows for clearer errors when a GeoDataFrame is created but has no
  geometry.
* TST: Add test util for comparing sequence (b/c assert_almost_equal seems
  to not work with shapely.
TST: Move geom_equals and geom_almost_equals to tests/util and use them
Add assert_geoseries_equal test util
TST/CLN: Guard geopy import and add skip tests if no geopy.
TST: Fix setattr issue with geometry property and more edge case tests
Merge pull request #54 from jtratner/change-geometry-v2

ENH: Allow geometry property to be set.
Merge pull request #58 from kjordahl/bug/cached_total_bounds

BUG: cached total_bounds don't reset if values are changed
Merge pull request #59 from jtratner/skip-and-guard-geopy

TST/CLN: Guard geopy import and add skip tests if no geopy.