Convert print statements to Python 3 style

Ran "2to3 -w -n -f print ./" and manually added imports.
Ran "^\s*print " and "\s+print " to find batch/shell scripts, comments and the like with embedded code, and updated them manually.
Also manually added imports to files, which used print as a function, but were missing the import.

The scripts still work with Python 2.
There are no intended behaviour changes.

Bug: 942522
Change-Id: Id777e4d4df4adcdfdab1b18bde89f235ef491b9f
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/tools/depot_tools/+/1595684
Reviewed-by: Dirk Pranke <dpranke@chromium.org>
Commit-Queue: Dirk Pranke <dpranke@chromium.org>
Auto-Submit: Raul Tambre <raul@tambre.ee>
diff --git a/git_number.py b/git_number.py
index 0d89d65..f3d2da7 100755
--- a/git_number.py
+++ b/git_number.py
@@ -21,6 +21,8 @@
 repo that it operates on in the ref 'refs/number/commits'.
 """
 
+from __future__ import print_function
+
 import binascii
 import collections
 import logging
@@ -278,7 +280,7 @@
   if not opts.no_cache:
     finalize(targets)
 
-  print '\n'.join(map(str, map(get_num, targets)))
+  print('\n'.join(map(str, map(get_num, targets))))
   return 0