Migration from Version 3 to 4 make this fail

Entry .uno:Open and .uno:OpenFromWriter are the same,
skip the entry .uno:OpenFrom

Change the operator, and a lot of comments
change the match in startWith for better reading
change test when old-cmd ".uno:Open"
change to the stephan solution

Change-Id: I0861c1e7d30b861acc753e3258707f3b6a338768
Signed-off-by: Stephan Bergmann <sbergman@redhat.com>