Merge pull request #490 from atlasapi/youview-multiple-environments

Ingest from YouView stage environment
Add equivalence jobs for youview stage
Use provided publisher when writing schedule block
Merge pull request #491 from atlasapi/youview-stage-equiv-job

Youview stage equiv job
Add schedule equiv updater for YouView stage
Improve error handling in ContentBuffer

If there are errors when flushing, carry on, rather than
fail.
Merge pull request #493 from atlasapi/pa-exception-handling

Improve error handling in ContentBuffer
Read PA brand/series summaries before write

Previously we just blindly wrote the summaries, which
meant that the items were always written, even if they'd
not changed. By reading first, we ensure that they are
only written if they change.
Merge pull request #494 from atlasapi/pa-brand-series-summary-read-before-write

Read PA brand/series summaries before write
Merge branch 'master' into stage

Conflicts:
	src/main/java/org/atlasapi/equiv/EquivModule.java
	src/main/java/org/atlasapi/remotesite/pa/ContentBuffer.java