Update all toplevel dependencies

Except for
- askama: latest revision doesn't play nice with latest rocket release
- time: not compatible with the cookies lib included with rocket
Fix cursor style on form buttons

Not sure why the cursor isn't already a pointer,
since they are clickable button elements.
But anyway, this ensures that the cursor displays the pointer style
as expected for enabled buttons.
Add nginx configuration for deployments
Update dependencies

Did not bump time to 0.3.5,
because `CookieBuilder::expires` included with Rocket
requires an older version of OffsetDateTime.
cargo update

Bump sub-dependencies
Don't allow `+` in tag names

This could be confusing, when `+` is used as the standard tag prefix.
Allow adding tags on submit resource

Users should be able to directly (and optionally) suggest tags.
The tags can be edited by editors before publication anyway.

Also accept the `+` prefix to tags in the tag editor.
So the syntax is: `[[+]tag_name] [[+]tag_name]...`
Refactor resource result into include file
Don't hide search help or tags list from anon users

Oops... this conditional was only supposed to hide the quick search,
because the starred/marked searches only makes sense if logged in.
Highlight and unlink selected tags in results

Part of some upcoming usability improvements to search results.
Tags in results don't need to be linked
when that tag is already part of the search query.
Not sure if should be highlighted, but we'll try it out.
Fix bug with warn when filter and logged out

It's supposed to only warn if the user is logged out.
Tidy search input help links
Add warning on filter by stars/tags and logged out

These filters are ignored when the user is logged out,
so warn the user.
Only show quick search links if logged in

Filtering by starred/marked only makes sense if logged in.

And use the git short revision string, instead of a timestamp.
This better reflects how this is used for cache control.

May also use this in future to display the build revision on the site...
Simplify local dev

- remove dependency on docker
- fix etet
Remove unused lefthook config file
Rename +m/+s tags to +marked/+starred

More verbose, but much clearer naming for the user.

Also add quick search links for the starred and marked tag filters.
Improve sql queries for resources to simplify types

Get rid of that pesky {NULL} in sql queries,
so we can simplify the resource.tags type
and associated logic.