Add a command `pass-goto-entry' for moving to any
entry in the pass buffer.
Update copyright notices.
* pass.el (pass--drop-dir-headers, pass--entries)
(pass--target-entry-pos): New internal functions.
(pass-goto-entry): New command; bind it to 'j'.
(pass-show-keybindings): Show it in the header.
(pass--display-keybinding): Update formatting to give enough space
for the new command description.
* test/pass-tests.el (pass-goto-entry-tests): Add test.
* README.md: Document the new keybinding.