starting to use java8 streams and lambda to reduce code.
 + clean some unused code + source file to functional java
WIP - converting to use lambdas for shorter (cleaner) code
WIP - converting to use lambdas for shorter (cleaner) code
converting to use lambdas for shorter (cleaner) code
converting to use lambdas for shorter (cleaner) code
changing ExpressionBuilder (was ExprBuilder) to be an interface instead of a class, using default methods.