v1.1.7 Provider, Feature, and Bugfix Update

Additionally supported authentification provider:

• Kanidm

New Features:

• Support of PKCE (Proof Key for Code Exchange)

Themes:

• Show suitable menu icons in all webtrees themes

Bugfixes:

• Also show sign in button labels in flash messages and on register page (fixes #19)

Languages:

• Updated German, Dutch, English AU, English GB