Fixes #50

This closes #40

This allows admin to edit these pages from the web, using Markdown. It
also dynamically loads information on those pages now, and makes loading
`pages` templates a little easier to find in the code / more explicit.

It requires this new schema change:

CREATE TABLE IF NOT EXISTS `appcontent` (
  `id` varchar(36) NOT NULL,
  `content` mediumtext CHARACTER SET utf8 COLLATE utf8_bin NOT NULL,
  `updated` datetime NOT NULL DEFAULT CURRENT_TIMESTAMP,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=latin1;

This closes T533

This helps with post importing and clients that want to support post
scheduling. It also changes how Collection.ForPublic() works, no longer
resetting the ID.

Closes T532

This now sends out a `Create` activity when a post is moved from a draft
to a blog.

This closes #9. Closes T526.

Previously this was only supported on
/api/collections/{alias}/posts/{id} -- this also allows it on
/api/posts/{id}, so things like `Announce`s work.

This closes #4

- New editor nav
- New backend nav
- Support for drafts
- Different footers on backend

This includes config changes, collections, posts, some post rendering
funcs, and actual database connection when the server starts up.