Refactor the docs to promote user functions

[robyoung]

The functions that users most often use are the matcher functions, however the docs show the internal matcher classes first. This means that users have to scan through a bunch of internal detail to get to the documentation they're most likely interested in. This change switches things around to just document the actual matcher functions.

[offbyone]

I like the idea, but I don't like that this version of the docs has dropped documentation on the classes entirely.

How about maybe a second section called "Matcher Internals" that does the same thing, roughly, but for the implementing classes, or -- and I know this'd be duplicative a bit -- uses automodule to make sure it shows all the internals. Then, the "Matcher Library" section will become a tighter bit of documentation for the library the way you've done here, but we'll still see all the gory details elsewhere. Ideally the matcher library will link to the relevant section of the matcher internals pages.

[offbyone]

Thanks! It'll update the latest pyhamcrest docs, and when we next do a release this'll become the stable format for the docs too.