Added new activities
Initial implementation of floating action button
Made "Add Event" screen, updated strings
Revert "Made "Add Event" screen, updated strings"

This reverts commit b0d1856da9b5acc9c511328a478b593cdc6a7ba8.
Revert "Revert "Made "Add Event" screen, updated strings""

This reverts commit a98ed11f4a59e23a7044977b9de6bd8d0f7f8016.
Updated strings
Added list activity (no implementation)
Updated TODO statements :sleepy: