Merge pull request #189 from kirknorth/master

Add Grid datetime routine
FIX: RSL reading now takes the actual time stamp from the ray instead of assuming monotonically increasing time
MAINT: refactor of rsl.py support for ray time stamps
Merge pull request #3 from jjhelmus/pr_190

MAINT: refactor of rsl.py support for ray time stamps
Merge pull request #190 from scollis/rsl-time-fix

FIX: RSL reading now takes the actual time stamp from the ray instead of...
BUG: Reading a corrupt sigmet file raises IOError

Reading a Sigmet file which is corrupt before the end of the first sweep
raises a IOError.  Only a warning is issue when the file contains one or more
complete sweeps.

Calling the read_sigmet function with debug=True will provide details of where
the file is corrupt.
Merge pull request #192 from jjhelmus/bug_sigmet_corrupt

BUG: Reading a corrupt sigmet file raises IOError
ENH: Initial support for reading ODIM_H5 files.

* Support for reading ODIM_H5 file containing PPI scans using
  `pyart.aux_io.read_odim_h5`.
Merge pull request #195 from jjhelmus/odim_h5

ENH: Initial support for reading ODIM_H5 files.
BUG: relative import in odim_h5 module.

Corrected bug with invalid import of Radar object by replacing
absolute imports with relative imports.
Merge pull request #196 from jjhelmus/odim_h5

BUG: relative import in odim_h5 module.