Also remove the now superfluous 'id show' command
And clean up the 'status' output a bit

In libpurple-speak, 'IM' is a conversation just between two people.

Will contain all functions currently available through the command
UI and make them available through signals.

Also started a new command UI which will work through the API.
Started pulling things out of the one source file.

Version to use in directory and file name can be specified in env
This fixes #94

This fixes #107.

This fixes #127.

This fixes #113.

If build-essential isn't installed on the system it complains about "No CMAKE_CXX_COMPILER could be found"

So far turning logging from axc on works.
Log level still ignored.

Rebuilding used to happen when it shouldn't, for instance on `make
install` after `make`.

The "Types of Prerequisites" section of GNU make manual describes this
situation.

The fix in the last commit uncovered that such messages do not
always have a "to" attribute (at least they do not with Prosody).
"Uncovered" means this was completely broken.

Additionally, lurch now ignores a decryption failure under specific
circumstances: If both sender and recipient are the own account,
and the error code is libsignal's "duplicate message", a warning
is written to the debug log and the message itself ignored, as it
was probably a carbon-copy.

Should be fully backwards compatible, future further cleanup is possible, but
not mandatory.

Like Redhat SuSE uses libxmpp instead of libjabber.
Fixes issue #98

Signed-off-by: Steffen Sledz <sledz@dresearch-fe.de>

Previously, the message was written to the sender's conversation.
In this case this is always the own account, which was probably
handled intelligently by libpurple in many, but not all, cases.

Might help with #52.

And update README.

This closes #40.

I think sending encrypted messages was leaking memory this whole time...

Found that the data I need is not in PurpleConv, but in JabberConv.
Replaced that and removed my own hashtables and presence parsing.