based on net-genconfig v1.5.8 - extracting the code to read an
inventory from a directory or file and then merge templates

net-genconfig will be reworked to v2.0.0 to use this library (stripping
all the local code out to do the same thing) and the version numbers,
at least initially, brought in line

'profiles' renamed 'templates'

device profile code generalised to handle all types of object (assuming
they're converted to use the 'templates' attribute): all use lists of
templates to support multiple inheritance (devices worked like this but
VLAN profiles did not) - anything at the second level of the inventory
can now use profiles, if desired

fatal problems now raise exceptions rather than exit() so these can be
trapped by the caller, if required

improved debugging messages to minimise extraneous output and give
clearer paths