[#1465] exclude more unlikely cominations
Merge branch 'master' into 1465-travis-half-jobs
Merge branch 'master' into 1465-travis-half-jobs
[#1510] Correct License Not Specified capitalization
pip >= 1.5 needs --allow-all-external

Starting from version 1.5, pip stopped downloading packages hosted in an
external site, even if there's a checksum in PyPI that we can check the
resulting package against. This breaks when downloading argparse==1.2.1 with
Python 2.6.

Here we allow all external downloads. It shouldn't be a security issue, as
we're still checking the package's hash against PyPI.

For more info, check
http://stackoverflow.com/questions/21021326/security-considerations-of-pip-allow-external
Merge pull request #1465 from ckan/1465-travis-half-jobs

Half Travis Jobs to speed them up.
Update datastore.rst

Duplicitous 'the'
Merge pull request #1511 from adamamyl/patch-1

Typo-fix (duplication) in datastore.rst:
Merge pull request #1510 from ckan/1510-license-not-specified-capitalization

Correct License Not Specified capitalization
Fixing small typo in comment
Merge branch 'master' into 1505-invite-to-organization-causes-error