Rather than evaling the `define` block in the
context of the matcher instance, eval the `define`
block in the context of the matcher instance's
* Fixes rspec#272.
`include` in `define` has a different meaning (module inclusion)
than `include` in the `match` block (using the `include` matcher to
* Better solution than rspec#194
for rspec#188. There's now
a `match` class method and a `match` instance method.
* Completely avoids issues we had to use hacks to solve before: