move function searching for a readline directly to SwRedlineTbl

It's more fun to roll one's own lcl_ function hidden somewhere, huh?

Change-Id: I8cad6ff7e829a58c68098bff23bd48343c3e5b6a
allow accepting/rejecting changes in a selection (bnc#874790)

Adds 'Accept Changes'/'Reject Changes' to the RMB popup if appropriate,
more convenient than handling them one by one.

Change-Id: I4e2670aa9fdacaaaa1b7ecca36b9c150c82e2e72