Fix two issues i had when using the new buildpack code:

mkdir: cannot create directory `/app//.profile.d': File exists
 !     Heroku push rejected, failed to compile Erlang app

cp: cannot stat `/tmp/buildpack_bmoaig71iviz/opt/otp.sh': No such file or directory
 !     Heroku push rejected, failed to compile Erlang app
Merge pull request #7 from gorenje/fix_profiile_d_copy

Fix two issues i had when using the new buildpack code: