explicitly ignore javadoc directories

.gitignore

  ~$3500NetworkedGraphicsSyllabus2019JulySeptember.doc
 /nbproject/build-impl.xml~
 /nbproject/private/
-**/javadoc/*
 /assignments/build/
 /assignments/dist/
+/assignments/dist/javadoc/
 /assignments/nbproject/build-impl.xml~
 /assignments/nbproject/genfiles.properties
 /assignments/nbproject/private/
@@ -12,6 +12,7 @@
 /examples/manifest.mf
 /examples/build/
 /examples/dist/
+/examples/dist/javadoc/
 /examples/nbproject/build-impl.xml~
 /examples/nbproject/genfiles.properties
 /examples/nbproject/private/