Delete everything from login_server and start putting things back.

Rebuilding from the ground up in a more incremental fashion from
now on. Small things adjusted like struct names, organization, etc.,
some things to be fixed later. The goal is to keep this source code
more compact and then to split it off into separate files once it
takes a more distinct shape instead of ending up being too spread
out again.

At this point there is only one error from the missing declaration
of handle_login.
Implement sending LOGIN welcome message.

I'm really getting bad about these commit messages.
Add Polarssl to project.

This will be used to replace the MD5 hashing with SHA256.
Update login_server CMakeLists with Polarssl linking.
Implement packet 0x1A (message packet) and flow for a nonexistant account.

Project builds and runs successfully, but is only tested up to a failed
login attempt where the user doesn't exist.
Update log file with expected naming.
Fix load_config and don't change directory back to start.

Welcome message and config dir were not being initialized correctly
and were causing chdir to be unsuccessful. Removed chdir back to the
start directory because it's easier for the server to handle logging
and loading anything else it needs during its lifetime.
Implement error logging for MySQL.
Include character port in server_config structure.
Finish basic implementation of LOGIN portion of the server.

There's very likely still functionality that needs to be added
(mainly init) but everything builds and the client makes it to
the CHARACTER portion, which is where the next development effort
is heading.
Fix and refactor lots of things.

I'm really getting bad about these messages. But really, lots of
misc fixes with emphasis on implementing the handling of the 0x93
login packet more effectively. The security packet (E6) still needs
to be fixed for when an account login is successful as it currently
causes the client to hang and refuse to disconnect. Removing it works
but messes up later 0x93 packets. Redirect (0x19) works as expected
if the security packet is removed.
Implement security packet, make minor cleanup changes, and stop using client send buffer.

The client send buffer at this point doesn't do much other than add
confusion, so it makes sense to just send the packet data directly.
Implement skeleton for packets the login server is responsible for.