Added neic module.

Thanks to David Ketchum.
Fixing attribution.
Removing obspy.iris documentation
PEP8
Update credits.rst
cleaning up obspy.neic

- renamed getWaveForm to getWaveform
- replacing duration with endtime in getWaveform (compatible with all
  other getWaveform methods)
- added some (for me) not working tests
refactoring obspy.neic - tests return now some results

@krischer: I wonder if the module name is correct

TODO: refactor test suite and remove second while loop in getWaveformNSCL
remove executable flags from text files
CHANGELOG
add obspy.neic to general infrastructure
add obspy.neic to general infrastructure (previous commit incomplete)
neic client: be compatible with NSLC order in all other Client.getWaveform routines + minor docstring fix
neic: close opened file and be pythonic
neic: delegate tmpfile handling to context manager
neic: cleanup merge of fetched stream

should handle..
 - duplicate blocks of identical data
 - split traces with perfectly aligned zero-gaps
neic: adapt test to change in getWaveform
neic: docs: add to module overview
neic: minor cleanup (user agent is not used..)
fix for previous commit
neic: cleanup (user agent string not used) and docstring cleanup