* 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