Add "Delete Collection and Items..." context-menu option

Also update collection/search deletion dialogs with better button text and no more "[JavaScript Application]"
Remove unnecessary version checking code
Context-menu string cleanup

- Remove all "Selected" from "Selected Item", because that's how a context menu works
- Change "Remove Selected Item" to "Remove Item from Collection" (fixes #122)
- Change "Delete Selected Item from Library" to "Move Item to Trash")
- Change "Remove" on Duplicate/Unfiled Items to "Hide" (fixes #122)
- Change "Create Parent Item from Selected Item" to "Create Parent Item"
Fix collection row selection issue on Windows
Update child attachment order when renaming attachment

Also show "1" next to child attachments with embedded notes
Merge locales from Transifex
Don't update item when tabbing through empty Date field