Update localservices to use httprouter from test suite

[tgross]

For #7

This updates our test suite to be compatible with the httprouter library that was added to gocommon. This results in a much more manual and explicit test suite setup because of some of the funky limitations in that library (which is really designed for performance, not testing... but to back that library our now would have ripple effects to our Terraform providers which I'd rather not take on now).

cc @misterbisson @chorrell

Test runs:

$ go test ./...
ok      github.com/joyent/gomanta       0.007s
?       github.com/joyent/gomanta/localservices [no test files]
ok      github.com/joyent/gomanta/localservices/hook    0.009s
ok      github.com/joyent/gomanta/localservices/manta   0.053s
ok      github.com/joyent/gomanta/manta 0.265s

$ go test ./manta -live
ok      github.com/joyent/gomanta/manta 8.790s

[tgross]

I've added support for Wercker CI to this PR as well. Successful builds look like this: https://app.wercker.com/joyent/gomanta/runs/build/582b74ba2e4c060100c22b60