vector: Changed boost operators layout.

boost::operators uses base class chaining. This means the declarations
of multiple operators are nested. Usually, this breaks any normal
layout scheme and boost operators must be treated specially when using
more than one operator.

Vector only uses ordered_field_operators, though, so we can treat it
normally.
rect: Default ctor test now uses vector's scalar ctor.
vector: Bashed initializer list ctor test.

vector_s doesn't have an initializer list ctor, so the 2-param init
form using curly braces calls the 2-param ctor. That test is already
covered by test-vector-parameterized-ctor.cpp, so this test is
superfluous.
rect_s: Explicitly implemented default ctor.
rect: Parameterized ctor.
vector: comparison_fixture_c is now a class template.
vector: Roughed in generalized comparison fixture.
test: Quick cleanup pass on generalized comp fixtures.
test: Moved comparison fixture up from vector.
test: Bashed stale vector comparison fixture module.
test: Trivial layout correction.
vector: Roughly generalized binary func fixture.
test: Moved binary func fixture up from vector.
test: Bashed stale vector binary func fixture module.
test: Added comments for binary_func_fixture_c.
rect: Equality.
rect: Ordering.
rect: Totally ordered.