No need to store result in IEx.Config
Optimize binary handling in Integer.parse and Float.parse

We have used the following commands to compile those files
with the appropriate optimization info:

    ERL_COMPILER_OPTIONS="bin_opt_info" elixir lib/elixir/lib/integer.ex
    ERL_COMPILER_OPTIONS="bin_opt_info" elixir lib/elixir/lib/float.ex

More info at www.erlang.org/doc/efficiency_guide/binaryhandling.html