bpo-30406: Make async and await proper keywords (#1669)

Per PEP 492, 'async' and 'await' should become proper keywords in 3.7.
diff --git a/Lib/test/test_tokenize.py b/Lib/test/test_tokenize.py
index 21eee6d..3520a67 100644
--- a/Lib/test/test_tokenize.py
+++ b/Lib/test/test_tokenize.py
@@ -759,7 +759,7 @@
     """)
 
         self.check_tokenize("async def foo(): pass", """\
-    ASYNC      'async'       (1, 0) (1, 5)
+    NAME       'async'       (1, 0) (1, 5)
     NAME       'def'         (1, 6) (1, 9)
     NAME       'foo'         (1, 10) (1, 13)
     OP         '('           (1, 13) (1, 14)
@@ -776,7 +776,7 @@
     await
 async += 1
 ''', """\
-    ASYNC      'async'       (1, 0) (1, 5)
+    NAME       'async'       (1, 0) (1, 5)
     NAME       'def'         (1, 6) (1, 9)
     NAME       'foo'         (1, 10) (1, 13)
     OP         '('           (1, 13) (1, 14)
@@ -787,12 +787,12 @@
     NAME       'def'         (2, 2) (2, 5)
     NAME       'foo'         (2, 6) (2, 9)
     OP         '('           (2, 9) (2, 10)
-    AWAIT      'await'       (2, 10) (2, 15)
+    NAME       'await'       (2, 10) (2, 15)
     OP         ')'           (2, 15) (2, 16)
     OP         ':'           (2, 16) (2, 17)
     NEWLINE    '\\n'          (2, 17) (2, 18)
     INDENT     '    '        (3, 0) (3, 4)
-    AWAIT      'await'       (3, 4) (3, 9)
+    NAME       'await'       (3, 4) (3, 9)
     OP         '='           (3, 10) (3, 11)
     NUMBER     '1'           (3, 12) (3, 13)
     NEWLINE    '\\n'          (3, 13) (3, 14)
@@ -802,7 +802,7 @@
     OP         ':'           (4, 6) (4, 7)
     NEWLINE    '\\n'          (4, 7) (4, 8)
     INDENT     '    '        (5, 0) (5, 4)
-    AWAIT      'await'       (5, 4) (5, 9)
+    NAME       'await'       (5, 4) (5, 9)
     NEWLINE    '\\n'          (5, 9) (5, 10)
     DEDENT     ''            (6, 0) (6, 0)
     DEDENT     ''            (6, 0) (6, 0)
@@ -815,7 +815,7 @@
         self.check_tokenize('''\
 async def foo():
   async for i in 1: pass''', """\
-    ASYNC      'async'       (1, 0) (1, 5)
+    NAME       'async'       (1, 0) (1, 5)
     NAME       'def'         (1, 6) (1, 9)
     NAME       'foo'         (1, 10) (1, 13)
     OP         '('           (1, 13) (1, 14)
@@ -823,7 +823,7 @@
     OP         ':'           (1, 15) (1, 16)
     NEWLINE    '\\n'          (1, 16) (1, 17)
     INDENT     '  '          (2, 0) (2, 2)
-    ASYNC      'async'       (2, 2) (2, 7)
+    NAME       'async'       (2, 2) (2, 7)
     NAME       'for'         (2, 8) (2, 11)
     NAME       'i'           (2, 12) (2, 13)
     NAME       'in'          (2, 14) (2, 16)
@@ -834,14 +834,14 @@
     """)
 
         self.check_tokenize('''async def foo(async): await''', """\
-    ASYNC      'async'       (1, 0) (1, 5)
+    NAME       'async'       (1, 0) (1, 5)
     NAME       'def'         (1, 6) (1, 9)
     NAME       'foo'         (1, 10) (1, 13)
     OP         '('           (1, 13) (1, 14)
-    ASYNC      'async'       (1, 14) (1, 19)
+    NAME       'async'       (1, 14) (1, 19)
     OP         ')'           (1, 19) (1, 20)
     OP         ':'           (1, 20) (1, 21)
-    AWAIT      'await'       (1, 22) (1, 27)
+    NAME       'await'       (1, 22) (1, 27)
     """)
 
         self.check_tokenize('''\
@@ -866,7 +866,7 @@
     OP         ':'           (3, 11) (3, 12)
     NAME       'pass'        (3, 13) (3, 17)
     NEWLINE    '\\n'          (3, 17) (3, 18)
-    ASYNC      'async'       (4, 2) (4, 7)
+    NAME       'async'       (4, 2) (4, 7)
     NAME       'def'         (4, 8) (4, 11)
     NAME       'bar'         (4, 12) (4, 15)
     OP         '('           (4, 15) (4, 16)
@@ -888,7 +888,7 @@
   async def bar(): pass
 
   await = 2''', """\
-    ASYNC      'async'       (1, 0) (1, 5)
+    NAME       'async'       (1, 0) (1, 5)
     NAME       'def'         (1, 6) (1, 9)
     NAME       'f'           (1, 10) (1, 11)
     OP         '('           (1, 11) (1, 12)
@@ -904,7 +904,7 @@
     OP         ':'           (3, 11) (3, 12)
     NAME       'pass'        (3, 13) (3, 17)
     NEWLINE    '\\n'          (3, 17) (3, 18)
-    ASYNC      'async'       (4, 2) (4, 7)
+    NAME       'async'       (4, 2) (4, 7)
     NAME       'def'         (4, 8) (4, 11)
     NAME       'bar'         (4, 12) (4, 15)
     OP         '('           (4, 15) (4, 16)
@@ -913,7 +913,7 @@
     NAME       'pass'        (4, 19) (4, 23)
     NEWLINE    '\\n'          (4, 23) (4, 24)
     NL         '\\n'          (5, 0) (5, 1)
-    AWAIT      'await'       (6, 2) (6, 7)
+    NAME       'await'       (6, 2) (6, 7)
     OP         '='           (6, 8) (6, 9)
     NUMBER     '2'           (6, 10) (6, 11)
     DEDENT     ''            (7, 0) (7, 0)