Reusable geometry cache

[patrickbr]

Split the Sweeper into two separate classes:

• Sweeper, which sweeps
• GeometryCacheManager, which handles geometry adding to cache, preprocessing, serialization

This is a major refactoring discussed with @ullingerc. The overall goal is to enable Qlever to parse geometries once on index build, and later re-use these parsed and preprocessed geoms during query time.

[patrickbr]

First step is done (there is now a GeometryCacheManager). This is already used in the tests and in main() and seems to work without any problems.

Next steps:

1.) also serialize the remaining parts of GeometryCacheManager to disk so that we can easily rebuild it in QLever during query.
2.) Create a SweepEventList class which holds the geom IDs relevant for the join. These may come from multiple cache, and the correct cache is selected by the upper 3 bits of the geometry ID returned from the GeometryCacheManager. Several goals here: enable "local" geometry caches during query execution for user-defined geometries, and allow a build of "local" sweep event lists. We also want the two sides of a join to be in separate event lists, as this enables some speedups in spatialjoin.

During the implementation of the first step I noticed a few smaller things which prevent (2) atm, but I have a few rough ideas how to tackle them.

[patrickbr]

Now has a SweeperEventList class, unclear so far where the geometryDuplicateRemoval should now reside in, so disabled atm (which is why the tests are failing)