Prevent infinite loop when a dbstructure_definition hook is orphan

Fix quoting style in DFRN::birthdayEvent()

- Add cascade option to dba::delete
- use cascade = false for orphan hook deletion

Better working with private forums

frio - add missing page styles for user setting pages

Revert "Moved .htconfig.php file & extracted Install business logic"

frio - fix default template if friendica is installed into a subdirectory

Moved .htconfig.php file & extracted Install business logic

frio - fix image upload for prv messages

Extracted install business functions to new Class `Install.php`

Contact requests from Diaspora for private forums aren't accepted automatically anymore

translation updates to DE, FI and PL

[TASK] Config: Add MySQL environment variables

Frio admin/users : follow up of  4861 - "more space"

to have more space

Change user table header "Account" to "Type": it use less space :-)

regenerated master messages.po file

IT, FI and ZH_CN translation updates

Add hidden input in newpassword console

Add space before Impressum.

The page /friendica/ contains an Impressum section which is activated with an AddOn.
Add more space after last paragraph of information, before impressum, because site
looks quite cramped otherwise.

Frio: add template for admin/users

- replace last a href=# with button
- use smallest breakpoint for panels footers

- move checkboxes on first column
- move select/deselect all as button group on panel footer
- use existing jquery in mod_admin.js for select/deselect all functionality
- add page content wrapper, without padding
- fix user avatar size in "pending deletion" table

[FEATURE] Install Script: Add first version

- Add Exception when password is empty