first step - it is slower in the implementation for now, but all cases
seems to be sorted out.
Drop Flagged() and IsSet() from solver. the solver wont care, and only
the assertion value does matter (exception for uninstall)
Fixes races conditions and make the DB Switchable. Also prepare inside
the CompilationSpec the tree of the deps to be built, and parallelize
only the building jobs.
Closes#7
Signed-off-by: Ettore Di Giacinto <mudler@gentoo.org>
Add CompilationSpecs type to handle slices of CompilationSpec, to
perform operation such as Unique() and Remove().
Add also dependencies and the spec associated to the Artifact, to track
how the artifact was generated.
Add revdeps compilation wrapper, and unit tests
