o Allow radius and presence modules to be turned off;
o don't override CFLAGS;
o don't duplicate error messages to the console;
o postgresql backend doesn't set NULL flag on results properly, so that
don't use VAL_NULL() macros on them;
o reconnect to MySQL db when necessary;
o relax transaction matching rules, so that it works with wider range of
phones;
o add some missed sanity checks in usrloc;
o ignore incoming UDP messages that are shorter than certain limin (128
bytes). They cannot be SIP messages anyway.
