Switch SilverStripe dependency from CSM to basics

Since the userswitcher can be used on sites that only use the core it makes sense to switch this dependency.

Switch SilverStripe dependency from CSM to framework

SS4 version of the switch to require only what is really needed

Subsites fixes + addFieldToTab instead of push

Fixed template path for (optional) Subsite switcher. Changed the method of checking for presence of Subsites module because this one is easier to overload. Config fields on Member are added to Tab Root.Main instead of pushed to the FieldList.

SS5 support fixes

Thanks @sunnysideup

Add SS 5 support

Thanks @sunnysideup for adding SS5 support

Added translatable text and screenshots

v1.1.2

Added screenshots and translations

Composer added

Composer