Add progress compatibility for PHP 5.5

Long story short, there was a backwards incompatible change to the
CURLOPT_PROGRESSFUNCTION callback arguments.
in visit_debug: check $value for true-ish value.
CS
Adding the option to combine URLs using strict RFC 3986 compliance while maintaining backwards compatibility with the erroneous way that Guzzle had previously implemented
Fix E_NOTICE on Header::parseParams() with empty text.
Merge remote-tracking branch 'thinkscape/hotfix/malformed-header-notice'
Cleaning up empty header checks.
Fix curl error when url contains #fragment.
Change preg_replace to substr+strpos.
Merge pull request #457 from Thinkscape/curl-error-url-with-fragment

Fix #453 - curl error when url contains #fragment.
Making the debug option show verbose cURL output
Working with older versions of cURL
Fixing timeout typoe
fixes a regression introduced in recent versions
Adding a change to ensure that libxml errors are buffered when disabling XXE loading in the Response::xml() method
Merge remote-tracking branch 'schmittjoh/urlRegression' into fixurlRegression
Using existing merge function
Added ability to define PostName. Fixes #442

Moved postname parameter to end of parameter list. Moved basename logic to constructor.

Fixed tests.
Switching from self:: to static:: when constructing Url in its factory method, thus using late static bindings which will enable easier subclassing of the Url class.
Fixed typos