Adds tests for GDAL not installed (#71)

* Adds tests for GDAL not installed

* typo in travis else

* proper matrix build

* semicolons...I write python

* updates test with conditional osr

* Proper pytest skipping enabled for conditional imports

* missed pytest import

* Typos

* Mixing pytest and unittest

* typos and imports

* typos city

* removes hasosr

* fixes wrapper for conditional gdal

* Removes test for non-available gdal