v0.6.0

Minor release including switch from rasterio to inpoly for some mask creation.

Minor Enhancements:

• Add a yaml file describing the mpas_tools dev environment #418
• Switch from rasterio to inpoly for signed distance masks #420

Clean up

• Update culling script to python3 #412
• Switch to file spec for the development env. #419

Bug fix:

• Fix invalid vertices in vertex transect masks #414

Contributors:

@xylar
@mark-petersen
@dengwirda
@milenaveneziani