`weechat-message-filter-functions': Modify text before sending.

From the docstring:

List of functions called in sequence before a line will be sent to the server.

The functions (a b c) are applied like (a (b (c input-string))).
If a function returns nil, evaluation will stop and the line is
ignored.

Signed-off-by: Moritz Ulrich <moritz@tarn-vedra.de>
Small docstring fix

Signed-off-by: Moritz Ulrich <moritz@tarn-vedra.de>
New module: weechat-alias. Define local command aliases in elisp.

Signed-off-by: Moritz Ulrich <moritz@tarn-vedra.de>
Run checkdoc on weechat-alias.

Signed-off-by: Moritz Ulrich <moritz@tarn-vedra.de>
Rename weechat-alias-command-prefix to weechat-alias-prefix.

Signed-off-by: Moritz Ulrich <moritz@tarn-vedra.de>
Implement double-ret for filtered messages:

If `weechat-message-filter-require-double-ret' is t and message filter
changes something, weechat.el will replace the text in the buffer,
requiring a second RET before sending it to the server.

Signed-off-by: Moritz Ulrich <moritz@tarn-vedra.de>
Remove one of my hooks from weechat-alias. Whoops.

Signed-off-by: Moritz Ulrich <moritz@tarn-vedra.de>
Rename weechat-alias to weechat-cmd.

Custom command functions now have the prefix 'weechat-command-'.

Signed-off-by: Moritz Ulrich <moritz@tarn-vedra.de>