Refactoring before cdb import improvement implementation

1) remove 'final' in loop parameters and private methods
2) remove public in interfaces
3) remove unnecessary casting
4) add {} for if operator
5) add @Deprecated for methods which marked as deprecated in comments
6) replace StringBuilder with simple string concatenation; since java 5 compiler can do this optimization by it self: http://docs.oracle.com/javase/specs/jls/se5.0/html/expressions.html#15.18.1.2
7) add more info into exceptions
8) move methods into class where it give most cohesion
9) make object fields final where it is possible
10) added DefaultDbLoaderDelegate to avoid all methods implementation where only one required