closes #79

* a single h-entry and h-card, where the h-entry has no URL, will result in a permalink page with that h-entry
* multiple h-entrys followed by an h-card is a feed

closes #77

* mf2+html
* mf2+json
* feed+json
* xml
* instagram/facebook/github/xkcd

returns a new property `post-type` next to `type`

closes #25

* adds test of instagram-atom feed with individual authors per item
* dedupes atom/rss title if it's a prefix of the content

closes #32

* removes the HTTP classes from this project and uses p3k-http library instead
* reorganizes the XRay classes into a psr-4 compatible folder
* moves controller autoload into -dev in preparation for turning this into a library (#17)

* closes #23
* major refactor of the methods for extracting properties to consolidate the logic
* hReview parsing is incomplete due to issues with the php-mf2 backcompat parsing. see https://github.com/indieweb/php-mf2/issues/107

* fields that should be URLs will now be omitted if the value was not a URL, such as when the value is `javascript:alert()`
* makes Mf2 class slightly more self-contained by duplicating the URL helper functions into it
* fixes tests to not cache responses in memcache