Fix loading of fiveam-asdf defsystem. (#161)

* Fix loading of fiveam-asdf defsystem.

Previously, we were forced to load that system by hand, when reading
the ASDF system definition. By pulling some code out, and by using
strings for class designators in shop3.asd's tester systems, we no
longer have to do this.

shop3/shop3.asd

@@ -195,27 +195,6 @@ minimal affected subtree."
 ;;; Testing
 ;;;---------------------------------------------------------------------------
 
-(asdf:load-system "fiveam-asdf")
-
-(defclass tester-cl-source-file ( cl-file )
-  ()
-  (:documentation "Special class that will have to recompile no matter
-what..."))
-
-(defmethod operation-done-p
-           ((o compile-op)
-            (c tester-cl-source-file))
-  "We are crushing the normal operation-done-p for compile-op, so that
-the tester files get recompiled, to take into account any changes to
-shop3."
-  (values nil))
-
-(defclass shop-tester-mixin ()
-     ()
-  (:documentation "Mixin that adds silent functioning of SHOP3."))
-
-
-(defclass shop-fiveam-tester (shop-tester-mixin fiveam-tester-system) ())
 
 (defsystem shop3/openstacks
     :depends-on (:shop3)
@@ -233,7 +212,7 @@ shop3."
 
 (defsystem shop3/test
     :defsystem-depends-on ((:version "fiveam-asdf" "2"))
-    :class shop-fiveam-tester
+    :class "fiveam-asdf:fiveam-tester-system"
     :test-names ((pddl-tests . :shop3)  ; 144
                  (protection-test . :protection-test)  ; 16
                  ;; all the following are now subsumed into all-shop3-internal-tests
@@ -270,7 +249,6 @@ shop3."
                           :components ((:file "common")
                                        (:file "warns-check")))
 
-                 (:file "silent-shop-test")
                  (:file "theorem-prover-tests"
                         :pathname "tests/theorem-prover-tests")
                  (:module "shop-pddl-tests"
@@ -378,7 +356,7 @@ shop3."
 
 (defsystem shop3/test-satellite
     :defsystem-depends-on ((:version "fiveam-asdf" "2"))
-    :class shop-fiveam-tester
+    :class "fiveam-asdf:fiveam-tester-system"
     :test-names (("SATELLITE-ADL-TESTS" . "TEST-SATELLITE"))
     :num-checks 80
     :depends-on ((:version "shop3" (:read-file-form "shop-version.lisp-expr"))
@@ -390,7 +368,7 @@ shop3."
 
 (defsystem shop3/test-unifier
     :defsystem-depends-on ((:version "fiveam-asdf" "2"))
-    :class shop-fiveam-tester
+    :class "fiveam-asdf:fiveam-tester-system"
     :test-names (("TEST-SHOP-UNIFIER" . "SHOP-UNIFIER-TESTS"))
     :num-checks 36
     :depends-on ("shop3/unifier" "alexandria")