remove force recompilation of classes from jooby:spec

[ajcamilo]

I was having issues with my build cycle and the main reason was because jooby:spec forks the compilation to generate the spec file and after this the default compilation occurs.

jooby:spec executes the build to the process-classes phase.

Besides my compilation problems (mainly because of ebean and querybean enhacement), another down side of this is that the compilation is much slower (2 compilations).

This PR just removes the execution of the process-classes and if the plugin is set to execute in the phase process-classes everything works as expected.

[coveralls]

Coverage remained the same at 99.886% when pulling 40070d5 on ajcamilo:master into 209a7ac on jooby-project:master.

[jknack]

I changed the project structure and your pull can't be merge it, sorry for that.

But don't worry going to pick your commit and merge them my self later (unless you want to do it :)

[ajcamilo]

rebase done 😉

[coveralls]

Coverage remained the same at 99.886% when pulling 9d1ad58 on ajcamilo:master into 8ae900f on jooby-project:master.

[jknack]

Merged it. Much appreciated!