Vector Layer Query optimization

[DamonU2]

Optimize queries for vector layers. Steps are all dependent on what the layer type allows. The steps are based on what is possible for ESRI Feature queries, and will need to be adjusted for other types.
Get record count first, and load features in batches accordingly.
Load batches in parallel.
Only load geometry initially.
Do not load properties until asked for - data table or feature clicked.
Exclude geometry when querying properties for data table.