Add yapf python formatter and format all files

yapf seems widely used in chromium. Adding here and
formatting all existing sources.

Change-Id: I5fd223a46cf3a00e6b7e6266850825b484af1558
diff --git a/tools/extract_linux_syscall_tables b/tools/extract_linux_syscall_tables
index 9252f26..4b2def0 100755
--- a/tools/extract_linux_syscall_tables
+++ b/tools/extract_linux_syscall_tables
@@ -20,7 +20,7 @@
   table = {}
   for line in data.splitlines():
     line = line.strip()
-    if line.startswith('#') or not(line):
+    if line.startswith('#') or not (line):
       continue
     parts = line.split()
     table[int(parts[0])] = 'sys_' + parts[2]