Nansat

New mappers for netcdf-cf files from AROME and ECMWF weather products. Updated opendap and Sentinel-1 mappers. Plus other small improvements and bug fixes.

Stable version of Nansat
Changelog:
- New OPENDAP mappers to access:
- OC CCI
- SST CCI
- METNO SIWTAC
- METNO OSISAF
- GLOBCURRENT
- All OpenDAP mappers now inherit from mappers/opendap:Opendap. Mappers ..._online are removed;
- Add DataForTestingOnlineMappers and TestOnlineMappers to end2endtests;
- Domain.write_map can add several patches to the map;
- mapper globcolour reads also PAR;
- mapper globcolour_l3b creates TMP file for netDCF4;
- mapper modis_l1 adds at least 30x30 GCPs from lon/lat bands;
- mapper obpg_l2 sets correct platform for SeaWiFS
- Mapper sentinel_1a can read all metadata from manifest and other XML files (also zipped);
- nansat.reproject strictly requires domain
- Unittests for Node are added
- More unittests for Nansat are added
- Unittests for PointBrowser are added

Stable version of Nansat
Changelog:
- README.yml with specifications of platform, sensor, etc. is added to mappers

Stable version of Nansat
Changelog:
- nersc-metadata replaced by py-thesaurus-interface

Stable version of Nansat integrated with [nansen-cloud](https://github.com/nansencenter/nansen-cloud), [nersc-vagrant](https://github.com/nansencenter/nersc-vagrant), [nersc-metadata](https://github.com/nansencenter/nersc-metadata), [conda-recipes](https://github.com/nansencenter/conda-recipes) and [nansat-lectures](https://github.com/nansencenter/nansat-lectures).

Main changes:
- mappers add standardized metadata (time_coverage_start, platform, instrument, etc);
- get_transect returns recarray;
- TravisCI uses miniconda;
- export2thredds works fine;
- adds random colorbar for a map;
- read OC CCI, OC SST, GLOB-CURRENT products
and many more ...