added possibility to read from SQlite file
updated documentation
reverting change and removing unneeded file
reverting all changes in RecoTauTag package
Merge pull request #4585 from jpavel/72x_taus_SQlite

Adding hooks to tau sequence to read from DB
Merge remote branch 'origin/CMSSW_7_2_X' into CMSSW_7_0_X