move tmp dir from edx-west/tmp to edx-west/ec2_cache

Per feedback from @feanil on PR #849, want our release branch to line up
with what we're pulling into master.

Going back to putting ssh connections in /tmp.  They have globally
unique names, putting in /tmp is consisten with other things, and having
them live in a dir named ec2_cache feels odd now.

playbooks/edx-west/tmp/.gitignore → playbooks/edx-west/ec2_cache/.gitignore

@@ -2,4 +2,5 @@
 
 !prod
 !stage
+!data
 !.gitignore

playbooks/edx-west/ec2_cache/stage/.gitignore

+*
+
+!.gitignore

playbooks/edx-west/prod-ansible.cfg

@@ -18,5 +18,5 @@ user=ubuntu
 
 [ssh_connection]
 # example from https://github.com/ansible/ansible/blob/devel/examples/ansible.cfg
-ssh_args= -o ControlMaster=auto -o ControlPersist=60s -o ControlPath=tmp/prod/ansible-ssh-%h-%p-%r
+ssh_args= -o ControlMaster=auto -o ControlPersist=60s -o ControlPath=/tmp/ansible-ssh-%h-%p-%r
 scp_if_ssh=True

playbooks/edx-west/prod-ec2.ini

@@ -3,6 +3,6 @@ regions=us-west-1
 regions_exclude = us-gov-west-1
 destination_variable=public_dns_name
 vpc_destination_variable=private_dns_name
-cache_path=tmp/prod
+cache_path=ec2_cache/prod
 cache_max_age=300
 route53=False

playbooks/edx-west/stage-ansible.cfg

@@ -15,5 +15,5 @@ user=ubuntu
 
 [ssh_connection]
 # example from https://github.com/ansible/ansible/blob/devel/examples/ansible.cfg
-ssh_args=-F stage-ssh-config -o ControlMaster=auto -o ControlPersist=60s -o ControlPath=tmp/stage/ansible-ssh-%h-%p-%r
+ssh_args=-F stage-ssh-config -o ControlMaster=auto -o ControlPersist=60s -o ControlPath=/tmp/ansible-ssh-%h-%p-%r
 scp_if_ssh=True

playbooks/edx-west/stage-ec2.ini

@@ -3,6 +3,6 @@ regions=us-west-1
 regions_exclude = us-gov-west-1
 destination_variable=public_dns_name
 vpc_destination_variable=private_dns_name
-cache_path=tmp/stage
+cache_path=ec2_cache/stage
 cache_max_age=300
 route53=False