* mh-alias.el (mh-alias-add-alias): Grand message and error string

* mh-alias.el (mh-alias-add-alias): Grand message and error string
unification. Use single sentence if possible by using semicolon. Don't
end message with punctuation. Don't need format with message. Quote
messages as in docstrings: use `' around symbols, \" for option
choices. Don't use quotes around %s.

* mh-comp.el (mh-complete-word): Ditto.

* mh-customize.el (mh-adaptive-cmd-note-flag-check)
(mh-scan-format-file-check): Ditto.

* mh-e.el (mh-refile-or-write-again, mh-previous-unread-msg)
(mh-delete-a-msg, mh-refile-a-msg, mh-next-unread-msg)
(mh-msg-num-width-to-column): Ditto.

* mh-identity.el (mh-identity-field-handler): Ditto.

* mh-index.el (mh-mairix-execute-search)
(mh-swish-execute-search, mh-swish++-execute-search)
(mh-namazu-execute-search): Ditto.

* mh-init.el (mh-variant-set): Ditto.

* mh-mime.el (mh-mh-to-mime-undo, mh-mml-forward-message)
(mh-secure-message, mh-mime-display): Ditto.

* mh-pick.el (mh-search-folder, mh-pick-construct-regexp): Ditto.

* mh-seq.el (mh-narrow-to-seq, mh-put-msg-in-seq, mh-read-seq)
(mh-read-range, mh-thread-container-subject): Ditto.

* mh-utils.el (mh-x-image-scale-and-display)
(mh-prompt-for-folder, mh-handle-process-error)
(mh-list-to-string-1): Ditto.