Now 'nfdc foo help', 'nfdc foo --help', and 'nfdc foo -h'
are all accepted as synonyms of 'nfdc help foo'.
Additionally, '--version' can be used in place of '-V'.
Change-Id: I070bb0ea9231a2642c40938377f1e9af2630b34e
Refs: #4503
Moving exit code to the context allows error handling routines to
rely only on the context.
Moving stdout and stderr streams to the context allows mocking in
unit tests, and allows sending output to a buffer for pre-processing
when we implement interactive mode.
refs #3864
Change-Id: Ibf59c12405d0eaca0597835cb2e30125b7f70adb
Davide Pesavento
Junxiao Shi