Remove iso8601 dependency

CloudKitty does not import and use this module directly,
no need to list it in the requirements.
This dependency was required before oslo_utils.

Change-Id: Ie323185b6006af306b09f814ac92c19049d94d5a

contrib/cloudkitty.spec.in

@@ -15,7 +15,6 @@ BuildArch: noarch
 BuildRequires: git
 BuildRequires: python-ceilometerclient
 BuildRequires: python-keystoneclient
-BuildRequires: python-iso8601
 BuildRequires: python-stevedore
 BuildRequires: python-oslo-messaging
 BuildRequires: python-setuptools
@@ -83,7 +82,6 @@ Group: System Environment/Base
 
 Requires: python-ceilometerclient
 Requires: python-keystoneclient
-Requires: python-iso8601
 Requires: python-stevedore
 Requires: python-oslo-messaging
 Requires: python-setuptools

requirements.txt

@@ -6,7 +6,6 @@ eventlet>=0.17.4
 keystonemiddleware>=2.0.0
 python-ceilometerclient>=1.0.13
 python-keystoneclient>=1.6.0
-iso8601>=0.1.9
 PasteDeploy>=1.5.0
 posix-ipc
 pecan>=1.0.0

rtd-requirements.txt

@@ -6,7 +6,6 @@ eventlet>=0.17.4
 keystonemiddleware>=2.0.0
 python-ceilometerclient>=1.0.13
 python-keystoneclient>=1.6.0
-iso8601>=0.1.9
 PasteDeploy>=1.5.0
 posix-ipc
 pecan>=1.0.0