The new requests library pulls in a chardet dependency that is in
conflict with coala packages. Pin the version of requests to ensure
we're pulling in a supported version.
Copied change by Thanh.
Change-Id: Ie0e18e5f370c584f11d2dddd39cdf59e5d141bc7 Signed-off-by: Daniel Farrell <dfarrell@redhat.com>