pom.xml: enforce that javac in 1.8.X is used. (#1267)
pom.xml: enforce that javac in 1.8.X is used. (#1267)

* pom.xml: enforce that javac in 1.8.X is used.

arifogel/batfish,batfish/batfish,dhalperi/batfish,batfish/batfish,dhalperi/batfish,intentionet/batfish,batfish/batfish,arifogel/batfish,dhalperi/batfish,intentionet/batfish,intentionet/batfish,intentionet/batfish,intentionet/batfish,arifogel/batfish