Edit proposal and remove "hosting" type from "Cost" section, since the goal is...

Edit proposal and remove "hosting" type from "Cost" section, since the goal is to let the monero core team host it.
And also remove the word "lifetime", since it is confusing. Lifetime was referring to the practice that a author/maintainer of a github repository is actively maintaining his code on his repository as long as he is the maintainer of that repository, which is usual practice on github, but I realize the word is probably confusing to others.