some refactor of lookup data.
Update Lookups.java
Update Lookups.java
Update AmberLookupsTest.java
Update Lookups.java
Merge remote-tracking branch 'origin/master' into dsc-123
added apis to add, delete and update lookup data.
minor code cleanup.
update the latest version in README.md
merged in the latest changes from master branch.
added indicator for a latest delete lookup entry, refactored to include review comments.
Merge pull request #121 from nla/dsc-123

merged.