[PATCH] parse_url rewrite

As clearly demonstrated buy bug report #16545, the current implementation of parse_url() function is extremely slow. I wrote a custom state machine parser to do the parsing in the place of the current regular expression. The result is code that takes a fraction of the time to run and in addition to running faster, resolves some bugs in the existing implementation of the parse_url() function. I've tested the code using a parse_url() test created by Derick, which can be found at php4/ext/standard/tests/strings/url_t.phpt. The new code passes the test admirably and is in excess of 30 times faster then the existing implementation. Please try the attached patch and let me know if there are any objections to replacing the current parse_url implementation with the one I propose. Ilia