watch-list in translate5 editor

A watch list for segments is implemented in the editor:

• in the toolbar with the save-, cancel- buttons for the opened segment a toogle-button "watch" is integrated
  → like a browser "favorite" button, with a star and separated by a divider line
• for the watch list the existing filter framework is used:
  • an additional hidden boolean column "watch" is added to the segment grid. The default value of the column is "no"
    → because of the "per user feature" the filter info does not come from segments table, but it is filtered in a "join" way, that means a specific column is not needed in the grid
  • on click of the watch-button the watch-column is set to yes
  • a button "watch list" is implemented next to the existing button "reset sorting/filtering"
  • on click off this button, a filter is set to show only the segments with "yes" in the watch-column
    → if another filter is set, display a notification, that perhaps not all watchlist segments are visible
  • the watch-property of the segment is saved to the db in the normal way - caution: no autostate and no segment changes and no history entry at this point!!!

=> The contents of this watch-list should be save per user - the next user in the workflow should NOT be able to see the contents of the watch-list of the previous one.