* moved $/testfilter.sh to $/util/testfilter.sh (updated Makefile accordingly)
* updated idea in Design.md
* renamed TestParse/TestFetch to TestSimpleParse/TestSimpleFetch.. more tests coming
* parse now sorts its results. test updated.
* moved regexp compilation to init instead of every time parse() is called
* misc comments and cleanup
* added test for fetching a known file and verifying its content matches
* add test for parsing a known string and verify URLs are extracted
* add test for a request which doesn't exist and verify 404 is received (canary test)
* add comments throughout test (for each test function)
* wrote (stupidly) simple fetcher which takes a URL, GETs it, and returns the body and error
* wrote (stupidly) simple parser which takes a string, parses out (src|href|xhref)="...", and returns a slice of the captured links
* added needed html files
swaits