This change adds switch cases for K_FOCUSGAINED and K_FOCUSLOST to the
input handling functions in ex_getln.c and terminal.c. The handling is
identical to what's found in edit.c (just calling apply_autocmds).
If one enters cmdline-mode by feeding `:` and sends a focuslost event (by
leaving the window for example) the text `<FocusLost>` will be inserted
into the command line. There is similar behaviour in terminal mode. This
patch corrects this behavior to fire the apropriate autocmd instead.
Fixes#3714