Add /tpo and and some spaces.

/tierpollopt or simply /tpo shows a Voice or above the tierpoll options. Plus, I simplified the process so now you no longer have to update /tierpoll but instead the variable tierspoll. I made it outside both commands so you don't have to update the same variable in both commands at once.
Merge pull request #77 from macrarazy/patch-33

Add /tpo and and some spaces.