Added javadoc comments to Main class

Javadoc comments for:
- Main class.
- Main class attributes.
- Main class methods.
Fix for my first pull request

Fix for my first pull request  to fit project requirements.

-Deleted some unnecessary lines.
-Deleted some trailing white spaces.
-Deleted unnecessary indentation.
-Changed tabs for spaces.
Changed tab for space
Merge pull request #10 from Garcel/garcel-branch

Added javadoc comments to Main class by Garcel