Add a config file for ocsharetools cmd line tool

[Torwag]

make ocsharetools look up log-in credentials e.g. under a users path config file e.g.
~/.ocsharetools.rc
User can mask this with chmod 600 ~/.ocsharetools.rc
this would
a) avoid that the command line history if full with user login-credentials
b) makes usage simpler

In addition the config file could have standard values for most of the possible parameters.