Extensive refactoring to move away from directly manipulating datastore
options and use local variables instead.
The initial template generation method has been redesigned to use an
external file via Erubi::Engine which is much cleaner vs. jamming a
multiline string into the module.
Response HTML from vCenter is now parsed with Nokogiri HTML vs. pulling
it out with regex.
Registered options have been reworked, following suggestions and
feedback. The use of VHOST in particular eliminates the need to pass
RHOSTS to the template and makes the module behave more closely to "real"
vCenter (i.e., always uses FQDN for the destination).
Added advanced datastore options to control the token lifetime
NOT_BEFORE and NOT_AFTER skew, in seconds. This also uncovered a bug with
the way I was deriving Zulu time which skewed based on the local system
time zone offset from Zulu; this has been fixed.
Corrected a stupid typo in the validate_fqdn method (don't need to check
for capital letters if the test string is always downcase...)
validate_idp_options now uses File.binread and can process certs in keys
in DER or PEM instead of just PEM.
Code optimization, particularly around error handling; other minor
tweaks based on improved understanding of the Framework's capabilities.
Many style changes and modifications based on suggestions and feedback.
Documentation was updated to reflect reality.
Spencer McIntyre