Remove the scala plugin (#442)
Remove the scala plugin (#442)

Datavec does not contain nor compile any scala code

Before:
mvn clean package -DskipTests=true  276.60s user 10.07s system 260% cpu 1:50.11 total

After:
mvn clean package -DskipTests=true  153.76s user 5.56s system 312% cpu 50.933 total
huitseeker/DataVec,deeplearning4j/DataVec,deeplearning4j/DataVec,huitseeker/DataVec