Improved core readability for split screen (~80 characters/line).
Removed unwanted whitespaces.
Removed unwanted whitespaces from specs.
Fixed decimal validator regexp with proper string delimiters.
More info: http://www.ruby-doc.org/docs/ProgrammingRuby/html/language.html#UL
Added specs to test price format validator with newlines (\n).
Merge pull request #11 from efmiglioranza/improve-code-readability

Improved code readability.
Removed unwanted whitespaces from code and specs.
Fixed decimal validator regexp with proper string delimiters and added specs.