Intercept abp:subscribe and adguard:subscribe links

[ameshkov]

This is useful for adding custom filter lists. For instance, from this website: https://filterlists.com/

[admitrevskiy]

Done (v3.3)

Testing instructions for QA:

• Reinstall AG
• Go to https://filterlists.com/
• Try to subscribe for any filter

Expected result:

• In app with not activated license you will see Promo activity
• In app with activated license you will see Add new Custom Filter dialog with filled url field

[ameshkov]

@admitrevskiy you should also test that it works on https://adblockplus.org/subscriptions

[admitrevskiy]

@ameshkov I've retested this issue with https://adblockplus.org/subscriptions and it works fine.
subscribe.adblockplus.org is replaced with with adguard:subscribe if protection is enabled.