Standardize skip_files to test_.+; rename support to test_support.

Standardize skip_files to test_.+; rename support to test_support.

This is largely a mechanical change. A few imports were reordered along the way.

The end goal is to symlink'ing test_support/ from within applications, to reduce
sys.path manipulation.

R=vadimsh@chromium.org
BUG=

[vadimsh, 2015-03-19 06:01:02]

https://codereview.appspot.com/215360043/diff/1/appengine/auth_service/PRESUB...
File appengine/auth_service/PRESUBMIT.py (right):

https://codereview.appspot.com/215360043/diff/1/appengine/auth_service/PRESUB...
appengine/auth_service/PRESUBMIT.py:22: from test_support import gae_sdk_utils
gae_sdk_utils is mostly unrelated to testing :( It is used from "gae.py" tool.
That's the reason I called it "support" in a first place (instead of
"testing_tools" for example), because it's not just for testing. It is a code
that supports development activities (testing, tooling), but not to be deployed
with components. I do not like putting gae_sdk_utils.py into "test_support".

"support" and "components" together look nice: you make a symlink to both, and
use "support" from tests and tools (and blacklist it in app.yaml), and deploy
"components". I don't see why it is any worse than "test_support" that
inconsistently includes code not related to testing.

https://codereview.appspot.com/215360043/diff/1/appengine/auth_service/tests/...
File appengine/auth_service/tests/frontend_handlers_test.py (left):

https://codereview.appspot.com/215360043/diff/1/appengine/auth_service/tests/...
appengine/auth_service/tests/frontend_handlers_test.py:26: 
eh, I like new lines between groups of imports, you don't. We'll keep making
this bikesheddings over and over.

[M-A, 2015-03-19 14:50:10]

Ok, I broke the CL locally and it became too large. I'll redo a smaller one.
Leaving comments for posterity.

https://codereview.appspot.com/215360043/diff/1/appengine/auth_service/PRESUB...
File appengine/auth_service/PRESUBMIT.py (right):

https://codereview.appspot.com/215360043/diff/1/appengine/auth_service/PRESUB...
appengine/auth_service/PRESUBMIT.py:22: from test_support import gae_sdk_utils
On 2015/03/19 06:01:01, vadimsh wrote:
> gae_sdk_utils is mostly unrelated to testing :( It is used from "gae.py" tool.
> That's the reason I called it "support" in a first place (instead of
> "testing_tools" for example), because it's not just for testing. It is a code
> that supports development activities (testing, tooling), but not to be
deployed
> with components. I do not like putting gae_sdk_utils.py into "test_support".

Ok so I split "support" in two:
- tool_support
- test_support

I added README.md to each to explain the difference. wdyt?
I agree that strictly speaking, we do not need to separate both but I think it's
nice to clarify this separation long term even if it is for 2 files.

> "support" and "components" together look nice: you make a symlink to both, and
> use "support" from tests and tools (and blacklist it in app.yaml), and deploy
> "components". I don't see why it is any worse than "test_support" that
> inconsistently includes code not related to testing.

The main downside is that now there will be one more symlink.

https://codereview.appspot.com/215360043/diff/1/appengine/auth_service/tests/...
File appengine/auth_service/tests/frontend_handlers_test.py (left):

https://codereview.appspot.com/215360043/diff/1/appengine/auth_service/tests/...
appengine/auth_service/tests/frontend_handlers_test.py:26: 
On 2015/03/19 06:01:01, vadimsh wrote:
> eh, I like new lines between groups of imports, you don't. We'll keep making
> this bikesheddings over and over.

This is because this confuses the difference between
stdlib/externallib/locallib/. Normally, you'd have:

import sys  # stdlib
...

from components import bar  # externallib
...

from server import foo  # locallib
...

For tests, this muddy up because of the test setup. But when externallib has
multiple subgroups, each become a separated with the same separator (an empty
line) than separating the 3 overall sections.

But yes it is bikeshedding, so I odn't mind too much as long as they are all the
same.

https://codereview.appspot.com/215360043/diff/20001/appengine/auth_service/te...
File appengine/auth_service/tests/replication_smoke_test.py (right):

https://codereview.appspot.com/215360043/diff/20001/appengine/auth_service/te...
appengine/auth_service/tests/replication_smoke_test.py:26: from tool_support
import gae_sdk_utils
This is the part I find interesting, smoke tests do not need test_support.