KnownIdentitiesPage: Put "Add identity" form after known identities list
- So clicking through pages of the known identities list doesn't involve scrolling.
KnownIdentitiesPage: Remove ancient throws declarations
- This was back from the days when WOT was so buggy that duplicate scores/trusts would occur frequently. Nowadays, this does not happen anymore. If those exceptions were thrown, there would be significant database corruption which isn't normal mode of operation. Therefore, the UI doesn't have to handle it.