[epic] eliminate the need to specify the catalog template type in render-template

[grokspawn]

We can reduce the level of knowledge that opm users need to have about our supported catalog templates if we require an explicit schema for each.

Steps to accomplish this:

• ensure existing templates enforce explicit schema #1331
• document basic template schema and generation from existing FBC #1336
• converge render command option passing #1332
  (for e.g. [verb] [file(s)] [options]) right now basic/semver templates already follow this format, but composite template with its two required imports does not presently
• move composite template parsing into the lib from the command #1333
• perform template recognition & command options parsing in the render-template command instead of template-specific #1334