factor out the M2Crypto check to flashproxy.keys
migrate reg methods to argparse
migrate flashproxy-client to argparse
more docs for reg methods
- mention how the client registration address is worked out
- add shorter usage synopses from man pages
fix flashproxy-client registration
- this ought to have been grouped together with c323a11f "migrate flashproxy-client to argparse" but it had already been reviewed, so I kept this extra commit
move common functionality and command-line options into flashproxy-common
- move keys.DEFAULT_FACILITATOR_PUBKEY_PEM into new reg module to be with other default-facilitator data
remove ignore_pubkey param, treat http as special case
unify common parts of build_register_command
Merge branch 'bug9975'

Use argparse instead of getopt and factor out much duplicate code.
rename facilitator binaries to have more "unique" names.

facilitator              -> fp-facilitator
facilitator.cgi          -> fp-registrar.cgi
facilitator-email-poller -> fp-registrar-email
facilitator-reg          -> fp-reg-decrypt
facilitator-reg-daemon   -> fp-reg-decryptd