Call lua_close when destructing TLuaInterpreter.
Merge branch 'release_31' into development

Call lua_close when destructing TLuaInterpreter.
Remove dead stats code from AliasUnit.
casts
get url
TMap::vertex
foo
Setup memory leak checking on MSVC in debug builds.
Add a feature for debug builds to prompt to attach a debugger.
Avoid macro max/min with parentheses.
Remove luazip lua bindings on windows.
Update to Communi 1.2.1, which is the new version of the irc library.
Make mpConsole in Host into a QPointer, so it is set to null whenever it is deleted.
Don't access mpConsole if it is null.
In situations where something tries to access mudlet (the class), after it is destructed, make it easier to tell what is going on.
Make HostManager a member of mudlet (the class) rather than a global singleton so that its lifetime is better understood.
Don't leak the string that defines the regex and since QByteArray's are null terminated and contiguous in memory, we don't need to copy them.
Fix deletion of the various types of user created objects. This probably doesn't fix all instances, but it should be much closer.
Fix memory leaks in the way pcre is used.
Boost includes <hash_set> on GCC unless BOOST_NO_HASH is defined which causes a deprecation warning on newer versions of GCC.