Allow numpy arrays to be passed by value into tasks (and inlined in the task spec). (#1816)

* Allow numpy arrays and larger objects to be passed by value in task specifications.

* Fix bug.

* Fix bug. Inline all bug numpy object arrays.

* Increase size limit for inlining args in task spec.

* Give numpy init different signatures in Python 2 and Python 3.

* Simplify code.

* Fix test.

* Use import_array1 instead of import_array.

python/ray/common/test/test.py

@@ -30,7 +30,9 @@ def random_task_id():
 
 BASE_SIMPLE_OBJECTS = [
     0, 1, 100000, 0.0, 0.5, 0.9, 100000.1, (), [], {}, "", 990 * "h", u"",
-    990 * u"h"
+    990 * u"h",
+    np.ones(3),
+    np.array([True, False]), None, True, False
 ]
 
 if sys.version_info < (3, 0):
@@ -60,8 +62,9 @@ class Foo(object):
 
 
 BASE_COMPLEX_OBJECTS = [
-    999 * "h", 999 * u"h", lst,
-    Foo(), 10 * [10 * [10 * [1]]]
+    15000 * "h", 15000 * u"h", lst,
+    Foo(), 100 * [100 * [10 * [1]]],
+    np.array([Foo()])
 ]
 
 LIST_COMPLEX_OBJECTS = [[obj] for obj in BASE_COMPLEX_OBJECTS]