Add solution for world101 tutorial (#1498)

Closes #1450.

## Demo

    scripts/play.sh -i data/scenarios/Tutorials/world101.yaml --autoplay

data/scenarios/Tutorials/world101.sw

@@ -0,0 +1,36 @@
+def tB = turn back end
+def tR = turn right end
+def tL = turn left end
+
+def m = move end
+def m2 = m;m end
+def m4 = m2;m2 end
+def m8 = m4;m4 end
+def m9 = m8;m end
+def m10 = m8;m2 end
+
+def mg = m; grab end
+
+def get_3_trees : cmd unit =
+  tB; m; mg; mg; mg; tB; m4
+end
+
+def make_harvester : cmd unit =
+  make "log"; make "log"; make "log";
+  make "board"; make "board"; make "board";
+  make "box";
+  make "wooden gear"; make "wooden gear";
+  make "harvester"
+end
+
+def get_lambda : cmd unit =
+  m10; tR; m9; harvest; tB; m9; tL; m10
+end
+
+def solution : cmd unit =
+  build {get_3_trees}; wait 16; salvage;
+  make_harvester;
+  build {get_lambda}; wait 50; salvage
+end;
+
+solution

data/scenarios/Tutorials/world101.yaml

@@ -56,6 +56,8 @@ objectives:
     condition: |
       try { as base {has "lambda"} } {return false}
     prerequisite: get_harvester
+solution: |
+  run "scenarios/Tutorials/world101.sw"
 robots:
   - name: base
     display:

test/integration/Main.hs

@@ -199,6 +199,7 @@ testScenarioSolutions rs ui =
         , testTutorialSolution Default "Tutorials/require"
         , testTutorialSolution (Sec 3) "Tutorials/requireinv"
         , testTutorialSolution Default "Tutorials/conditionals"
+        , testTutorialSolution Default "Tutorials/world101"
         , testTutorialSolution (Sec 5) "Tutorials/farming"
         ]
     , testGroup