terminate with exit code of last command executed

Make sure that return code of triggered command gets propagated to the
application's entry point.

In interactive mode, meta-command shall exit with the return code of the
last command executed. Note that exit is also a command (returning 0 by
default).

Resolves ticket #174
exit interactive mode only when LmiTerminate is raised

Do not take into account the return value of executed command when
deciding whether to stop the shell. Terminate only when LmiTerminate is
raised.
spec: added hardware subcommand library
updated changelog, bumped version

This is a last release of lmi meta-command hosted on github. It will
move into openlmi-tools repository hosted on fedorahosted.

Bumped version of storage library to 0.0.3

Updated spec.