beta testing fixes and release

this MR fixes issues, that popped up while testing 1.5.0RC1

• fix circumvention settings strings
• ensure circumvention options are enabled on first run when connecting through a invite code
• Always show automatic circumvention settings. If a provider doesn't support bridges, this setting still configures the obfuscation of the API communication.
• fix storing and reloading introducer when switching provider
• fix resetting specific circumvention protocols when switching a provider since we don't know a priori which circumvention protocols another provider supports