Improve performance when loading paired normal alignment from WGS tumor alignment

[Nicklas Nordborg]

There are some wizards in the DNA WGS pipeline (eg. ASCAT, WGS variant calling, etc) that require a tumor/normal pair. We are always starting out with a list of tumor alignments and before we can generate a list to choose from we need to figure out if there is a normal alignment to pair with. This requires that we follow all links up to the Patient item and then down again to the aligned sequences. This is a bit time-consuming since it require a lot of database queries. It particularly annoying in the ASCAT wizard since when doing extra runs with custom parameters it is only possible to select a single item every time.

It would be nice if the time to load the list could be improved. For example, it should be possible to cache the information for some time since it is rarely changing.

[Nicklas Nordborg]

In 8097:

Fixes #1677: Improve performance when loading paired normal alignment from WGS tumor alignment

The "transform" functionality that we are using from the BASE API already have a caching functionality. So we can use that by wrapping the factory instance with a SourceItemTransformerWithCache.

The default timeout in the cache is 20 minutes which is a bit short so we create a CustomCacheTransformContext that uses a 3 hour timeout instead.

The cache is used by the ASCAT wizard and the two WGS variant calling wizards.