Updates the version number in the meta. (#159)

* Updates the version number in the meta.

* Update meta.yaml

* Build to hash

This should be using the short hash now.

* Update meta.yaml

* Update meta.yaml

recipe/meta.yaml

 
 package:
   name: usgscsm
-  version: "0.1.0"
+  version: {{ environ.get("GIT_DESCRIBE_TAG", "") }}
 
 source:
   git_url: https://github.com/USGS-Astrogeology/CSM-CameraModel.git
 build:
-  string: dev
+  string: {{ environ.get("GIT_DESCRIBE_HASH", "") }}
 
 requirements:
   build: