CMake workarounds for ubuntu capnproto 0.6.1 compatibility

[ryanofsky]

No description provided.

[Sjors]

That did the trick for me, although (perhaps unrelated), make test says it can't find any.

[ryanofsky]

That did the trick for me, although (perhaps unrelated), make test says it can't find any.

Thanks for testing! make test not doing anything is expected because ubuntu 0.6.1 package doesn't include the libkj-test library, so the mptest build is skipped

[Sjors]

This also fixed #26, except for make test, which throws

Test project /Users/sjors/dev/libmultiprocess/build
    Start 1: mptest
Could not find executable /Users/sjors/dev/libmultiprocess/build/mptest
Looked in the following places:
/Users/sjors/dev/libmultiprocess/build/mptest
....
Unable to find executable: /Users/sjors/dev/libmultiprocess/build/mptest
1/1 Test #1: mptest ...........................***Not Run   0.00 sec

0% tests passed, 1 tests failed out of 1

[ryanofsky]

make test says it can't find any.

To clarify, if you're seeing error:

No tests were found!!!

with capnp 0.6.1 this is expected because the test can't be built.

But if you're seeing:

The following tests FAILED:
          1 - mptest (Not Run)
Errors while running CTest

that's a different problem. You need to run make all test instead of make test in that case (https://stackoverflow.com/questions/733475/cmake-ctest-make-test-doesnt-build-tests). I'll update the readme to reflect this