use {obj:key} as a way to pass an object and not only strings to templates

As mentioned at the mail list[0]:

"So I need another way how to pass a *list* as data structure from
the defaults/project down to the job-template definition, similar to
what can be done with "{variable}" for strings."

[0] http://lists.openstack.org/pipermail/openstack-infra/2014-February/000799.html

Closes-Bug: 1281038
Change-Id: I5b04ddb52e537fedd2d05795e91011afd92f2295
fix the literalinclude reference to least-load test

Change-Id: I38a933c06e9d28ae1a580d26494a30e7385ee36f
add retry-count in general.py

implement retry-coutn in general.py;
update doc and add test fixtures

Change-Id: Ifeb4fb645ad0e4bc12d41ef4481aca1888a4041a
Add support for Slave Utilization plugin

Change-Id: I4243fddf2f08a09671757b503fae2a890f2d820e
Merge "Add support for Slave Utilization plugin"
Merge "fix the literalinclude reference to least-load test"
Merge "use {obj:key} as a way to pass an object and not only strings to templates"