Organize eval mechanism (1)
Add tests
Organize unit tests. Place them in an independent package.
Create a test suite package.
Create a unit test suite.
Remove old tests.
Organize error message
Uniform exception type to 'IllegalArgumentException' when an invalid
parameter is given.
Remove unused methods in NumCast
Add tests
Add Unit test suite
Move Arbitris's example to test directory from src directory.
Ignore djunit setting file.