Changed recipe_modules base paths to be abstract entities in their own right.

scripts/slave/recipe_modules/path/example.expected/win.json

 [
   {
     "cmd": [
       "/bin/echo",
       "[SLAVE_BUILD]\\foo"
     ],
     "name": "step1"
   },
   {
     "cmd": [
@@ skipping 42 matching lines @@
   {
     "cmd": [
       "echo",
       "[TMP_BASE]\\prefix_b_tmp_2"
     ],
     "name": "print prefix_b"
   },
   {
     "cmd": [
       "echo",
-      "[BUILD]\\scripts\\slave\\recipe_modules\\path\\resources\\dir\\file.py"
+      "RECIPE_MODULE[path]\\resources\\dir\\file.py"
     ],
     "name": "print resource"
   },
   {
     "cmd": [
       "python",
       "-u",
       "\nimport sys\nfrom common import chromium_utils\n\nchromium_utils.RemoveFilesWildcards(sys.argv[1], root=sys.argv[2])\n",
       "*.o",
       "[SLAVE_BUILD]"
     ],
     "name": "rmwildcard *.o in [SLAVE_BUILD]",
     "~followup_annotations": [
       "@@@STEP_LOG_LINE@python.inline@@@@",
       "@@@STEP_LOG_LINE@python.inline@import sys@@@",
       "@@@STEP_LOG_LINE@python.inline@from common import chromium_utils@@@",
       "@@@STEP_LOG_LINE@python.inline@@@@",
       "@@@STEP_LOG_LINE@python.inline@chromium_utils.RemoveFilesWildcards(sys.argv[1], root=sys.argv[2])@@@",
       "@@@STEP_LOG_END@python.inline@@@"
     ]
   }
 ]