Fix deprecation warnings
Fix deprecation warnings

* Errors#on have been deprecated
* Errors#[] now always returns an Array

codeforcroatia/alaveteli,andreicristianpetcu/alaveteli,andreicristianpetcu/alaveteli_old,10layer/alaveteli,nzherald/alaveteli,codeforcroatia/alaveteli,4bic/alaveteli,andreicristianpetcu/alaveteli,obshtestvo/alaveteli-bulgaria,obshtestvo/alaveteli-bulgaria,4bic/alaveteli,Br3nda/alaveteli,nzherald/alaveteli,10layer/alaveteli,petterreinholdtsen/alaveteli,TEDICpy/QueremoSaber,Br3nda/alaveteli,nzherald/alaveteli,datauy/alaveteli,TEDICpy/QueremoSaber,obshtestvo/alaveteli-bulgaria,andreicristianpetcu/alaveteli_old,Br3nda/alaveteli,andreicristianpetcu/alaveteli_old,TEDICpy/QueremoSaber,andreicristianpetcu/alaveteli,petterreinholdtsen/alaveteli,petterreinholdtsen/alaveteli,petterreinholdtsen/alaveteli,codeforcroatia/alaveteli,andreicristianpetcu/alaveteli_old,datauy/alaveteli,10layer/alaveteli,andreicristianpetcu/alaveteli_old,andreicristianpetcu/alaveteli,4bic/alaveteli,Br3nda/alaveteli,codeforcroatia/alaveteli,obshtestvo/alaveteli-bulgaria,Br3nda/alaveteli,petterreinholdtsen/alaveteli,nzherald/alaveteli,TEDICpy/QueremoSaber,datauy/alaveteli,4bic/alaveteli,obshtestvo/alaveteli-bulgaria,4bic/alaveteli,andreicristianpetcu/alaveteli,TEDICpy/QueremoSaber,nzherald/alaveteli