Update dependency noblogs/wp-mat to v0.1.4

See merge request !338

This reverts commit 524d28fd.

These interfere with JSON-LD activitypub requests because
apparently the '; profile="..."' part is matched by that humongous
rule 920600 regexp and ModSecurity thinks it's a charset.

Attempts to fix the content negotiation caching issue #134.

Update dependency johnpbloch/wordpress to v6.4.1

See merge request !337

Apparently gotosocial uses it for profile discovery.

Modern footer patches

See merge request !336

Update dependency wpackagist-plugin/activitypub to v1.1.0

See merge request !335

Update dependency wpackagist-plugin/wp-super-cache to v1.11.0

See merge request !334

Update dependency wpackagist-theme/twentyeleven to v4.5

See merge request !324

Update dependency johnpbloch/wordpress to v6.4.0

See merge request !323

Remove caching from pages ending with a / which MAY (or may not, more
likely) help in resolving issue #134.

Update the list of mobile user agents.

Update dependency noblogs/wp-mat to v0.1.3

See merge request !322

The cache/.htaccess mechanism should actually be moved into
the apache2 config, instead of the current hackish solution...