Fixing access to task "parameters" property in DSL
Fixing access to task "parameters" property in DSL

Change-Id: I046430ffb77abf2d462c89050e9e28e67fa72816

openstack/mistral,dennybaa/mistral,dzimine/mistral,dennybaa/mistral,StackStorm/mistral,openstack/mistral,TimurNurlygayanov/mistral,StackStorm/mistral