hookup_moveoff: error handling and ini settings

hookup_moveoff.tcl:

do not supply defaults if items are not in inifile -- use
component defaults. This allows external applications to net
and set the pins with sole control.

add ini provisions for min, max limit values

moveoff_gui:

no option for initial offset pin setting as that could
conflict with and extrnal app controlling the moveoff component.

+fix text in moveoff.comp
+remove some dead code
Signed-off-by: Dewey Garrett <dgarrett@panix.com>
hookup_moveoff.tcl: eliminate hardcoded threadname

Signed-off-by: Dewey Garrett <dgarrett@panix.com>