- Create a trait Moops::TraitFor::Keyword::dirty

- Create a trait Moops::TraitFor::Keyword::mutable

- Document the Moops::TraitFor::Keyword mechanism

- An assertion mechanism for use within methods/functions.

	assert { ... };

Normally, this keyword would be rewritten to:

	if (0) { ... };    # should be optimized away

Under EXTENDED_TESTING/AUTHOR_TESTING/RELEASE_TESTING/AUTOMATED_TESTING,
it would be rewritten to:

	die "Assertion failed" unless do { ... };
