Update year of copyright at README.md
Merge pull request #60 from rogeriopradoj/patch-1

Update year of copyright at README.md
- Inserts prime number validation

Signed-off-by: Kleber Hamada Sato <kleberhs007@yahoo.com>
Corrects the year (2012) at Copyright information

Signed-off-by: Kleber Hamada Sato <kleberhs007@yahoo.com>
Modifies if, else and for code structure.
- Modifies PrimeNumber.php to accept zero value or a number under zero.
  Returns: false

- Inserts PrimeNumberTest.php file with the Unit Test.

- Inserts PrimeNumberTest.php file with the exceptions validation.

Signed-off-by: Kleber Hamada Sato <kleberhs007@yahoo.com>
- Inserts copyright comments in PrimeNumberTest.

- Modifies the exception class name to PrimeNumberException and modifies
  the copyright current year to 2012.

Signed-off-by: Kleber Hamada Sato <kleberhs007@yahoo.com>
Change file PrimeNumberTest to PrimeNumberTest.php

Signed-off-by: Kleber Hamada Sato <kleberhs007@yahoo.com>
Fix problem with validation return (returns a boolean type now).

Signed-off-by: Kleber Hamada Sato <kleberhs007@yahoo.com>
Fix exception messages

Signed-off-by: Kleber Hamada Sato <kleberhs007@yahoo.com>
Merge pull request #61 from kleberhs007/prime_rules

Prime rules - Prime Number validation
Correct method from testInvalidFormattedCpf to testInvalidSlug, because
this method verifies a slug , not a CPF number.

Signed-off-by: Kleber Hamada Sato <kleberhs007@yahoo.com>
Merge pull request #63 from kleberhs007/correct_slug

Correct method from testInvalidFormattedCpf to testInvalidSlug
Insert validation, tests and exception for perfect square numbers.

About perfect square numbers:
Perfect square numbers are numbers which is a product of some integer
with itself. A square root of a perfect square numbers is always a integer
number.

Signed-off-by: Kleber Hamada Sato <kleberhs007@yahoo.com>
Merge pull request #65 from kleberhs007/square_root_rules

Insert validation, tests and exception for perfect square numbers.
Added test for #64
Added test for #64
Fix #64
Whitespace bugging travis?
Removed incomplete filter/sanitize support