lib/oeqa/utils/decorators.py: decorators for test methods

lib/oeqa/utils/decorators.py: decorators for test methods

Some skip decorators meant only for test methods, providing
some kind of test methods dependency.
They are used together with a test method name not a condition.
These are complementary to python's unittest skip decorators.

(From OE-Core rev: 79cb89648702aa80ec986e0026c62948de905b87)

Signed-off-by: Radu Moisan <radu.moisan@intel.com>
Signed-off-by: Stefan Stanacar <stefanx.stanacar@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>