Add support for config file

[delphidabbler]

A configuration file that can specify default options.

This will avoid having to keep providing the same command line options.

[delphidabbler]

Some simple commands that soverride the hard wired state will need to be rewritten to take parameters.

E.g --iso-date overrides the built in default local date. This will need to be replaced by something like date-basis that takes iso and local parameters

[delphidabbler]

Not implementing this for v3