update LAS/LAZ point cloud formats to registered IANA media-types

[fmigneault]

Overview

The LAS/LAZ point cloud formats used to employ the generic application/octet-stream.
The preferred and registered IANA media-types should be used.

This avoids applications using application/octet-stream as "arbitrary data" to associated it to point cloud formats, which might not apply and break downstream processes that would detect .las/.laz extensions.

Related Issue / Discussion

n/a

Contribution Agreement

(as per https://github.com/geopython/pywps/blob/master/CONTRIBUTING.rst#contributions-and-licensing)

• 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