Remove forgotten "is None".

user.ANON is a property that returns bools only.
close #1292
make this a link
Add danishtariq to security.txt for #1536
Merge branch 'master' into fix-sign-out
Add test to confirm the fix.
Alter homepage caching not to cause InternalError.

The change is based on the following test. You need two separate
connections to the db. On the first run:

    create table a (i int4);
    insert into a (i) values(1);
    begin;
    delete from a;

Now on the second connection run:

    select * from a;

That does not block and returns "1". The thing is that we can freely
update the table "a" in a transaction and not block parallel reading
of the original data in the table.

Open question: Does Heroku have some autovacuming on? If not we should
turn it on or the homepage tables will grow beyond bounds (the deleted
data is expunged only by a vacuum run).
Fix failing test (tables no longer recreated).
Merge pull request #1524 from gittip/fix-sign-out

Remove forgotten "is None".
Bump version to 10.1.29
Bump version to 10.1.29-dev
Add failing test for tip out of range.
Catch BadAmount when tip out of range.
Merge pull request #1537 from gittip/1536-ack

Add danishtariq to security.txt for #1536
Add failing test and fix for #1422.
Merge pull request #1559 from gittip/fix-receipts

Add failing test and fix for #1422.
Bump version to 10.1.30
Bump version to 10.1.30-dev
Tell Sentry about all raised Responses

And tag sentry entries with a response code (1xx, 2xx, ... 5xx, n/a).
We're using barely any of our sentry quota, so we may as well start
logging more stuff there (assuming it doesn't affect performance, but
I can't imagine that sentry is our bottleneck).

This came up because we were trying to debug a 403 that @zwn is seeing
with trying to update his take. We're not sure where it's coming from
and right now we're not even sending that to stdout. With this change we
should at least an exception reference ID on stdout and the full info in
Sentry.
Merge pull request #1547 from gittip/fix-homepage-race

Alter homepage caching not to cause InternalError.