fails:Hash#<= returns false when receiver size is larger than argument
fails:Hash#<= returns false when receiver size is the same as argument
fails:Hash#<= returns true when receiver is a subset of argument or equals to argument
fails:Hash#<= returns false when keys match but values don't
fails:Hash#<= raises a TypeError if the right operand is not a hash
fails:Hash#<= returns false if both hashes have the same keys but different values
fails:Hash#<= returns true if self is a subset of the other hash
fails:Hash#<= returns false if self is not a subset of the other hash
fails:Hash#<= converts the right operand to a hash before comparing
fails:Hash#<= returns true if both hashes are identical
