First healer: cleric or friar?

Wanted to roll my first healer. From friar I like the idea that sometimes I may change playstyle from full-healer to hybrid melee-healer.

Is friar going to have any chance to get invited in 8v8 (as full-healer) or that spot is just for clerics?

If answer is yes i'm going with friar. Otherwise with cleric.

ps. any must-have addon as healer? I'm totally newbie