Merge pull request #140 from kandread/patch-1

Removed credentials.

Do not make post ReST calls to Earthdata server.

Avoid column name conflict in cultivar query.

Fixes #70. Adds potential evaporation to VIC outputs.

Fixes #89. Use Earthdata module to download MCD15.

Directly extract links from Earthdata websites.

Fixes #90. Account for empty cultivar name.

Fix bug in DSSAT soils script.

Tested ingestion of PERSIANN data.

Fixes #93. Add support for PERSIANN precipitation data.

Fixed variable referenced before assignment.

Fixed missing crop definition when instantiating DSSAT model object.

Fixed formatting error in fertilizer application.

Change definition of fertilizer parameters.