build: Fix some module dependencies in mesher.
build: Fix module dependencies in solver.

 * write_seismograms depends on specfem_par.
 * Some new ASDF dependencies.
 * Several files depend on module created from write_seismograms.
build: Fix module dependencies in auxiliaries.

Don't build ADIOS targets if not configured with it. Add some
dependencies for modules used with ADIOS files. Correctly define phony
targets.
build: Simplify linker rules using automatic vars.

We can use $@ and $+ to get target and dependencies, which simplifies
the linker rules a lot. This is especially useful for the auxiliaries
directory, where there are several varied executables.
Merge pull request #40 from QuLogic/parallel-build

Parallel build fixes