allow custom UOM reference for literal IO

[davidcaron]

Overview

Currently, the only UOMs allowed when serializing an input are degree, meter and unity (see pywps.OGCUNIT). With the new 'watchdog' process, the inputs are always serialized, so these units are the only ones allowed.

I think that leaving the responsibility to the PYWPS service implementation to provide the UOM reference could be a simple solution to this.

Contribution Agreement

• I'd like to contribute [feature X|bugfix Y|docs|something else] to PyWPS. I confirm that my contributions to PyWPS will be compatible with the PyWPS license guidelines at the time of contribution.
• I have already previously agreed to the PyWPS Contributions and Licensing Guidelines

[coveralls]

Coverage increased (+0.08%) to 74.26% when pulling d11ce24 on davidcaron:allow-custom-uom-reference into 7126011 on geopython:master.

[cehbrecht]

@jachym This PR just extends the current UOMs implementation. We could add more common UOMs to the OGCUNIT list:

pywps/pywps/__init__.py

Line 80 in 7126011

OGCUNIT = {

[cehbrecht]

@davidcaron merged. Thanks for this contribution :)