allow users with reserve permission on secret systems to see them

Bug: 1066586
Change-Id: I3d8dc495ce7e7b62f87c57a99440038f7ed037ba
external tasks

A recipe task no longer needs to reference the task library, instead the
job XML can specify a "fetch URL".

Based on a patch contributed by Bill Peck <bpeck@redhat.com>.

Bug: 1057459
Change-Id: Ib3b5415c623c01343228447d3cf4a0298a9bcd70
record task version in each recipe-task

Bug: 576304
Change-Id: I76987182c27b5db8ae8c808890491accddab79ee
lab controller API to allow harnesses to update task name and version

Bug: 1057459
Change-Id: I96498bfd52fd18d92af492ee3006381d55c5acce
beaker-repo-update: add missing trailing slash to base URL

Change-Id: Ic90bd7eff143bdfdcb3395a4676f1011b8218395
Merge branch 'release-0.15' into develop

Updated the test case for bug 1066586 to reflect the fact that 0.16+ has
an explicit 'view' permission.

Conflicts:
	IntegrationTests/src/bkr/inttest/server/selenium/test_csv_export.py
	IntegrationTests/src/bkr/inttest/server/selenium/test_system_search.py
	Server/bkr/server/model.py
Merge branch 'develop' into new-system-page