Issue #401 - Adapted code to work with subscriptions.json

This MR for #401 (closed) contains the following changes:

• Based on #402 (closed)
• Updated mock subscriptions.xml with subscriptions.json from adblockpluscore
• Made adjustments to desktop-options and mobile-options based on integration notes
• Use "recommendations" naming convention to differentiate subscription objects from recommendations taken from subscriptions.json
• Use template string instead of string concatenation in loadRecommendations()