pcp updates: more containers fixes for 3.10.7

[Mark Goodwin <mgoodwin@xxxxxxxxxx>]

Nathan, please also cherry-pick these two - only affects the containers build.

Changes committed to git://pcp.io/markgw/pcp/pcp.git master

commit 9b0f7b29efc9c45de22ee74baf81607eeb5736ad
Author: Mark Goodwin <mgoodwin@xxxxxxxxxx>
Date:   Wed Sep 16 10:19:46 2015 +1000

    pcp-pmie container: remove /proc bind mount, it conflicts with --pid=host
    
    For the pcp-pmie container, same change as commit bafb33eac62.
        modified:   build/containers/pcp-pmie/Dockerfile


Also, the following commit in my tree doesn't seem to have been merged :

commit bafb33eac6226fc92c3a3da424581184b7d3e765
Author: Mark Goodwin <mgoodwin@xxxxxxxxxx>
Date:   Wed Aug 5 15:09:49 2015 +1000

    containers: remove /proc bind mount, it conflicts with --pid=host
    
    Docker v1.7.1 doesn't allow -v /proc:/proc and --pid=host since this
    is a redundant and conflicting configuration. Remove the bind mount.
    
        modified:   build/containers/pcp-collector/Dockerfile
        modified:   build/containers/pcp-monitor/Dockerfile
        modified:   build/containers/pcp-pmlogger/Dockerfile
        modified:   build/containers/pcp-testsuite/Dockerfile