Merge pull request #345 from wasi0013/master

Added Python and AWK implementation of Harshad Number
Linear Search with Java Tested with junit
Merge pull request #346 from mitogh/master

Linear Search with Java Tested with junit
Added README for Ackermann
Ackermann's function with Ruby tested with Rspec
ackerman function with PHP tested with PHPUnit
Ackermann's function with Java tested with JUnit
Remove duplicate files
Merge pull request #347 from mitogh/master

Ackermann's function with Ruby tested with Rspec
Added Average in Python