This enables users to add a signature to all blog posts, and update it from a single location.

Requires database migration with: writefreely db migrate

Closes T582

Ref T661

This notifies the user that the remote user doesn't exist, instead of
showing a blank page.

Ref T627

- Export the func
- Remove commented-out code
- Use log, not fmt for debug messages
- Remove named return parameters
- Use standard var naming schemes
- Fix spacing in queries and remove unnecessary chars

Previously, any password-protected collection on a suspended account
would prompt visitors for a password, and *then* take them to the "not
found" page. This fixes that.

This fixes a panic from a nil user when calling u.IsSuspended().
Instead, this checks and calls IsSuspended() on `owner`.

This changes all variables and functions from using Suspend{ed} to using
Silence{d} as well as documentation, errors and logging.

Some of the work needed to have the backend match user-facing wording.

Ref T661

From u.Status == UserSuspended to u.IsSuspended()

Ref T661

- update error messages to be correct
- move suspended message into template and include for other pages
- check suspended status on all relevant pages and show message if
logged in user is suspended.
- fix possible nil pointer error
- remove changes to db schema files
- add version comment to migration
- add UserStatus type with UserActive and UserSuspended
- change database table to use status column instead of suspended
- update toggle suspended handler to be toggle status in prep for
possible future inclusion of further user statuses

(https://github.com/writeas/writefreely/pull/195)

there it updates the table to include the handle.

migrations WIP

intermediate page (WIP) that shows the user profile page url

this changes the helper IsJSON to take a request instead of a string,
allowing to check multiple headers. In this case both Content-Type and
Accept.

With the var there now, this makes the code a bit more readable.

Includes:

* AP Collection fetching via canonical URL
* AP Collection fetching via API
* AP Post fetching via canonical URL
* AP Post fetching via API

Ref T693

This renders all requests for that user's posts, collections and related
ActivityPub endpoints with 404 responses.

While suspended, users may not create or edit posts or collections.

User status is listed in the admin user page

Admin view of user details shows status and now has a button to activate
or suspend a user.

GetCollections and GetPublishableCollections now take a hostname
parameter to allow setting the collecion hostname.

All collections used in memory now have their hostname set.

this changes GetPinnedPosts to accept an includeFutre bool, which
returns future dated pinned posts when true.

instead of updating it later. This is more correct behavior, prevents an
additional query, and ensures that potential collection-creation when
claiming posts also respects the default (which it didn't before).

Ref T675

instead of linking to posts only on a user's blog.

Ref T681

This adds a new config value: `chorus` that signifies an instance is
more about the Reader view than individual blogs / writers. When
enabled, user navigation will show on all pages, including About,
Reader, and Privacy (ref T680).

It also uses different collection templates that keep the instance-wide
navigation at the top of the page, instead of the author's name --
again, branded more for the collective than the individual.

Ref T681

This adds a new `default_visibility` config value that lets an instance
admin set the visibility of newly created collections.

Ref T675

This is the crucial part where the hostName is needed for federation and
API clients. This change at least lets us know when we mess up like this
so the issue is easier to catch in the future.

This moves `hostName` to the `Collection` struct, where it's needed. The
field is populated after successful `GetCollection...()` calls.

This isn't the cleanest way to do things, but it accomplishes the goal.
Eventually, we should accept the AppCfg to `GetCollection...()` calls,
or make them `App` methods, instead of `datastore` methods.

Ref T613

We load it always, no need for a user config UI

This is a first stab at having a configurable code highlighting option,
similar to the MathJax rendering option. This change makes a checkbox
in the settings for code highlighting using the highlightjs.org
library.
What works: code highlighting in multi-user env is like I would
expect. single and anon(?) needs work

Things to resolve/consider:
- does the .IsCode test for code highlighting need to stay? At least
this and that should use the same version of the highlight.js lib.
- can the common templating part be 'included' somehow?
- the anon vs single-user vs multi-user code is not completely
clear (to me)
- bring js to local instead of cloudfare cdn (perhaps combine with
MathJax)

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