Changes

pySim-shell: do not show user home path in help text

At the moment, the help text for the --csv option shows the path to
the users home. This is due to the default value, which is dynamically
generated. Let's use a static string with "~/" and resolve the full
path later when we need it.

Related: SYS#7725
Change-Id: Ied8b1e553de8f5370369c4485a2360906c874ed2