Added updates and refactored code

[mscr06]

Points Looked at:

1. Refactor existing code as it has lot of raw data.
2. Kept main logic code as minimal as possible by extracting enums, constants into new files.
3. Used enum values as holidays list for a year(2013 doesn't make sense) as it changes every year, better solution would be to read property file outside the codebase.
4. Kept the code in accordance with sonarqube quality check.
5. Have written sample main method test file. We can use JUnit if we move to MVC totally.

P.S: GIF is from Hackers movie :)