Add another mime type for Excel spreadsheets (patch from Peter)
Add another mime type for Excel spreadsheets (patch from Peter)

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