use proxy headers for determining service urls (#177)
Merge branch 'master' into issue_177
remove code which stripped scheme from redirect urls
Merge pull request #180 from slipstream/issue_177

pass proxy's scheme to SlipStream service and use for redirect URLs
Generating a restricted and time unlimited cookie for SS Client.

This commit also contain the following improvements:
    The cookie generated for SlipStream Client now contain the RunId.
    This cookie allows to access only to resources needed for the corresponding run.
    Improved the architecture of SlipStream Resources.

This commit correspond to the merge of the following pull request: https://github.com/slipstream/SlipStreamServer/pull/182
Merge branch 'master' into autoscale-add-delete-instances