Web Installer (#504)

* simplify setup command

* add installer page

* add route for installer

* adjust gitignore

* set colors globally

* add "unsaved data changes" alert

* add helper method to check if panel is installed

* make nicer

* redis username isn't required

* bring back db settings command

* store current date in "installed" file

* only redirect if install was successfull

* remove fpm requirement

* change "installed" marker to env variable

* improve requirements step

* add commands to change cache, queue or session drivers respectively

* removed `grouped` for better mobile view

.env.example

@@ -4,6 +4,7 @@ APP_KEY=
 APP_TIMEZONE=UTC
 APP_URL=http://panel.test
 APP_LOCALE=en
+APP_INSTALLED=false
 
 LOG_CHANNEL=daily
 LOG_STACK=single