Replaced spring framework with robospring.
Changed ethereumj-core build to android-library.
Disabled BlockStoreImpl until we make it android compatible( use InMemoryBlockstore ).
Disabled antlr4 dependencies.
Commented some dependencies(needs testing before enabling).
Excluded dom4j and org.jboss.spec.javax.transaction dependencies (problems with android).
Change to netty 4.0.18.Final (this seems to work with android; latest 4.1 and 5.0 presented some problems; needs additional testing).
- Convert ethereumj-studio build from Maven to Gradle as well
- Extract common build elements to top-level build.gradle
- Update top-level README accordingly