Terminal, Web and Clocks user docs

[Ekaterina Gerasimova <kittykat3756 gmail com>]

Hello all,

gnome-terminal user docs have been updated for 3.12. Existing strings
are very unlikely to be touched unless a patch makes it in for this
release, in which case the change will be minor and only to a <gui>
tag. New stings may be added, but I think this is unlikely.

epiphany user docs have also been updated for 3.12. Existing strings
are very unlikely to be touched, new strings may be added (also
unlikely).

gnome-clocks user docs had almost no changes for 3.12 and are finished.

Happy translating!