update gemspec with license
Initialize @next_line
Improve uom support.

Include an extensive list of mappings, including all of the Energistics
units in witsmlUnitDict.xml. The strategy is to map any unit encountered
in a LAS file by first lowercasing it, then looking it up in the uom
mapping table. Support using an external mapping file with the -m option.
Add some units to the default uom.json.

So that we can translate md.las
0.1.4
Added comments for uom_file feature. Bring up to 0.1.4.