temporary fix for FirstRun/LastRun wrong data type
remove tier0mode from PhEDExInjector

The Tier0Mode as originally implemented won't work and it's functionality will be taken over by some new generic mechanism.
Merge pull request #5522 from hufnagel/remove-tier0mode

remove tier0mode from PhEDExInjector
Merge pull request #5472 from amaltaro/cast-runNumbers

temporary fix for FirstRun/LastRun wrong data type