Fix accidental forkbomb in previous commit.

protoc wrapper ended up calling itself.
diff --git a/generator/protoc b/generator/protoc
index 0fd5506..4c4053b 100755
--- a/generator/protoc
+++ b/generator/protoc
@@ -6,12 +6,24 @@
 from nanopb_generator import invoke_protoc
 
 if __name__ == '__main__':
-    # Add script directory to path so that protoc-gen-nanopb gets found
+    # Add argument so that protoc-gen-nanopb gets found
     if getattr(sys, 'frozen', False):
         mypath = os.path.dirname(sys.executable) # For pyInstaller
     else:
         mypath = os.path.dirname(__file__)
-    os.environ["PATH"] = mypath + os.pathsep + os.environ["PATH"]
 
-    status = invoke_protoc(['protoc'] + sys.argv[1:])
+    if os.path.isfile(os.path.join(mypath, "protoc-gen-nanopb.exe")):
+        protoc_gen_nanopb = os.path.join(mypath, "protoc-gen-nanopb.exe")
+    elif os.name == 'nt':
+        protoc_gen_nanopb = os.path.join(mypath, "protoc-gen-nanopb.bat")
+    else:
+        protoc_gen_nanopb = os.path.join(mypath, "protoc-gen-nanopb")
+
+    args = sys.argv[1:]
+
+    if os.path.isfile(protoc_gen_nanopb):
+         args = ['--plugin=protoc-gen-nanopb=%s' % protoc_gen_nanopb] + args
+
+    print(args)
+    status = invoke_protoc(['protoc'] + args)
     sys.exit(status)
diff --git a/generator/protoc-gen-nanopb.bat b/generator/protoc-gen-nanopb.bat
index e6cf187..48a4aa9 100644
--- a/generator/protoc-gen-nanopb.bat
+++ b/generator/protoc-gen-nanopb.bat
@@ -9,4 +9,4 @@
 :: --plugin= on the command line.
 
 set mydir=%~dp0
-python "%mydir%\nanopb_generator.py" --protoc-plugin
+py -3 "%mydir%\nanopb_generator.py" --protoc-plugin