Mea culpa. It was possible an error caused `require` to
not be reset, causing possible errors in the future.

Fixes #35.

- Merge `list` into `help`.
- Use `table.concat` to remove trailing comma.

Also minor fixes.

Also minor style fixes.

This allows configuring the mod from the GUI.

Fixes an issue with `hooks.lua` calling the (old, disabled)
`require` function.

Follows #23

Allow server admin to specify how long until a reconnect occurs after a timeout (default 600 seconds) without having to modify the core code.

Debian's LuaSocket packages are broken.  Then seem to
package the 5.1 version of the library as simply a copy
of the 5.2 version; however, the libraries are incompatible.
Additionally, the package seems to take a number of
different names depending on the version of the distro.
However, the LuaRocks package seems to be fine, so install
that first and then install LuaSocket through LuaRocks.

This caused bot to fail to connect to servers protected with passwords.

Reported by reactor.

The underlying IRC library is now available as irc.lib.

Also rename README.txt to README.md and update it.