1. change package name of zats test cases 2. fix ant build by update classpath and lib/ext
add checker to check whether zkless-engine is installed in build file
Merge pull request #197 from hanhsu/fix-build-for-lessc

add checker to check whether zkless-engine is installed in build file
Bug ZK-2564: vm.items not sync after window serialization and deserialization
delete B01848FormBindingUpdateTest.java, issue will be fixed in 8.0