[SPARK-4821] [mllib] [python] [docs] Fix for pyspark.mllib.rand doc

+ small doc edit
+ include edit to make IntelliJ happy

CC: davies  mengxr

Note to davies  -- this does not fix the "WARNING: Literal block expected; none found." warnings since that seems to involve spacing which IntelliJ does not like.  (Those warnings occur when generating the Python docs.)

Author: Joseph K. Bradley <joseph@databricks.com>

Closes apache#3669 from jkbradley/python-warnings and squashes the following commits:

4587868 [Joseph K. Bradley] fixed warning
8cb073c [Joseph K. Bradley] Updated based on davies recommendation
c51eca4 [Joseph K. Bradley] Updated rst file for pyspark.mllib.rand doc.  Small doc edit.  Small include edit to make IntelliJ happy.

Conflicts:
	python/docs/pyspark.streaming.rst
	python/pyspark/mllib/feature.py

python/pyspark/mllib/__init__.py

@@ -32,29 +32,4 @@
 import rand as random
 random.__name__ = 'random'
 random.RandomRDDs.__module__ = __name__ + '.random'
-
-
-class RandomModuleHook(object):
-    """
-    Hook to import pyspark.mllib.random
-    """
-    fullname = __name__ + '.random'
-
-    def find_module(self, name, path=None):
-        # skip all other modules
-        if not name.startswith(self.fullname):
-            return
-        return self
-
-    def load_module(self, name):
-        if name == self.fullname:
-            return random
-
-        cname = name.rsplit('.', 1)[-1]
-        try:
-            return getattr(random, cname)
-        except AttributeError:
-            raise ImportError
-
-
-sys.meta_path.append(RandomModuleHook())
+sys.modules[__name__ + '.random'] = random