Remove mistral from global requirements

Historically, to write Mistral actions you would need to depend on
Mistral itself. However, with the introduction of mistral-lib this is no
longer required. The only consumer of mistral-as-a-library within
OpenStack was tripleo-common. It has been fully migrated to mistral-lib
(see depends-on) and the requirement can thus be removed.

Change-Id: I0a99c19d3cbcfbb396b09c008aff7a379a273d4c
Depends-On: I7ae2e0e4dbca6c02ed8ceedc066ca35eeb13c322

global-requirements.txt

@@ -109,7 +109,6 @@ lxml>=2.3,!=3.7.0  # BSD
 Mako>=0.4.0  # MIT
 marathon>=0.8.6  # MIT
 microversion-parse>=0.1.2  # Apache-2.0
-mistral!=2015.1.0,>=3.0.0  # Apache-2.0
 mistral-lib>=0.2.0  # Apache-2.0
 mitmproxy>=1.0.2;python_version>'3.0'  # MIT
 monasca-common>=1.4.0  # Apache-2.0

openstack_requirements/tests/files/upper-constraints.txt

@@ -51,7 +51,6 @@ nose===1.3.7
 click-spinner===0.1.7
 nosehtmloutput===0.0.5
 waitress===1.0.2
-mistral===4.0.0
 os-refresh-config===6.0.0
 jsbeautifier===1.6.11;python_version=='3.4'
 jsbeautifier===1.6.11;python_version=='3.5'

upper-constraints-xfails.txt

@@ -1,4 +1,2 @@
 # Format is
 # <dependency that is incompatible>==<version>;<list,of,affected,packages>
-
-SQLAlchemy==1.1.10;mistral,tripleo-common

upper-constraints.txt

@@ -61,7 +61,6 @@ nose===1.3.7
 click-spinner===0.1.7
 nosehtmloutput===0.0.5
 waitress===1.0.2
-mistral===4.0.2
 os-refresh-config===7.0.0
 jsbeautifier===1.6.14;python_version=='3.4'
 jsbeautifier===1.6.14;python_version=='3.5'