Possibility to change logo and leading text in settings

[hermansc]

Hi,

I guess many want to use this project in their organization or similar - and thus many would probably like to change the logo and leading text, perhaps also styling, in the settings.

[tlaundal]

Yeah.

Many of the forks have only changed the name and icon. Maybe also add a setting to remove direct connections? And when we get LDAP support, the register button.