A capability may be something like providing a folder of files, or just a data dictionary, and/or an API
capability handler - a package/namespace which may provide validation and standardised ways of looking up provider data registered (or not) using register_capabilityname
capability provider - a package which registers as providing one or more capablities. registered using register_package
the capabilitylist is a list of 2-element lists where the first element is the capabilityname and the second element is a (possibly empty) dict of data relevant to that capability A capabilityname may appear multiple times. ie a package may register that it provides the capability with multiple datasets.
return a boolean indicating the existence of a capability
Arguments:
- capname - string indicating the name of the capability
Returns: 0 1