Pipeline, execution and schedule views performance issues fix to 2.2.x develop

[eea03]

Copy of #547

Resolves #546
partly resolves #544

[skodapetr]

Just a note to consider ..
Some of those views utilize DbCachedSource

https://github.com/UnifiedViews/Core/blob/feature/pipelineAndExecutionViewsPerformance/frontend/src/main/java/cz/cuni/mff/xrg/odcs/frontend/doa/container/db/DbCachedSource.java

This class in fact already "do" some caching. It may be reasonable to do the changes there rather than add another caching layer for each component separately.

[eea03]

Yes I am aware of the existing cache mechanism. However these caches back up the table data itself and they use the database views and corresponding Java objects (PipelineView / ExecutionView).
The methods for evaluating permissions and others causing so much selects require single Pipeline / Execution objects.
In order to reuse the existing caches we would have to reimplement quite a big amount of code.

I am aware that this is not an optimal solution to have 2 caches but at least in eDemo we need a quick fix of these performance issues so we implemented it this way