Several changes

* bl-projects:
  + Rename base-dir property to dir-base.
  + Remove cmd-run property.
  + Change semantics of build-dont-prepend property to build-prepend-dir-base.
  + Add run-change-to-dir property.
* Always clear hooks after a successful/failed compilation and don't rely on
  clients to do so.
* Use correct paths when building project.
* Use correct paths when running the project's binary.
* Use correct paths when launching gdb.
* Pass arguments, if any, to project's binary when running it.
* Restore last buffer after launching gdb.