Add documentation to example parameter file generation configuration file.

Also changed input var SUBSET_LENGTH TO SUBSET_DAYS
Merge branch 'feature/documentation' into develop
Merge branch 'release/rvic.0.0.1'
Updates to support routing to streamflow gauge stations

- add gridx, gridy, routx, and routy attributes to point object.
- add Pandas dependency for csv IO
- add latlon2yx for mapping between coordiantes and indicies (better for irregular grid)
- simplify passing of source and outlet variables
- add outlet name to parameter file
Merge branch 'develop' of github.com:jhamman/RVIC into develop