explains when to use Float.parse/1 and that String.to_float will not deal with integer fmt strings
bypass warning
fix mistake on test
fix doc line's length and test one more time
Merge pull request #2873 from eksperimental/float

improve and examples for Float.parse/1 and String.to_float
Merge branch 'master' of https://github.com/elixir-lang/elixir