Add facebook as a place to find rentals in life-in-taiwan.md

[Russell-Shean]

I found all my previous rentals in Taiwan on Facebook, so I added a sentence about Facebook being an option for finding rentals too. I'm not sure about my grammar or location of the sentence! :D

[johncliu]

Perhaps add a name of a FB group or two? Please add a space after the period of the first sentence, and Facebook is normally capitalized. Thanks.