Major mode for decrypting monoalphabetic substitution ciphers.
Lower-case letters enter plaintext.
Upper-case letters are commands.
The buffer is made read-only so that normal Emacs commands cannot
The most useful commands are:
Uses keymap `decipher-mode-map', which is not currently defined.
M-x decipher-digram-list Display a list of all digrams & their frequency
M-x decipher-frequency-count Display the frequency of each ciphertext letter
M-x decipher-adjacency-list Show adjacency list for current letter (lists letters appearing next to it)
M-x decipher-make-checkpoint Save the current cipher alphabet (checkpoint)
M-x decipher-restore-checkpoint Restore a saved cipher alphabet (checkpoint) (fn)