[should-dsl] Two new branches

[Rodrigo Manhães]

Hi all,

i've pushed two new branches to my fork.,

[https://github.com/rodrigomanhaes/should-dsl/tree/better-failure-messages-for-custom-function-matchers]
improves (at least from my point of view) the messages generated by
matchers defined as functions (but this will break all messages for
preexisting matchers of this kind). It's an attempt to make function
matchers more useful.

[https://github.com/rodrigomanhaes/should-dsl/tree/alternate-operator]
proposes an alternate operator for the cases in which the __or__
operator cannot be used. See
[https://github.com/hugobr/should-dsl/issues/12] for details. This is
a workaround, not really a fix, but I think it is the only thing we
can do about it. And, of course, we have to document the problem as a
contraindication in some cases (e.g. Ludibrio stubs).

[]'s
Rodrigo