Removing js build files
Revert "Removing js build files"

This reverts commit 9a62cedc8be973417473954196a122bf73e2f111.
Removed js build files
Refactored interfaces and library 'part of' for dart-sdk revision 0.1.2.0_r15641
Merge pull request #3 from financeCoding/refactor_interface_keyword

Refactor interface keyword