New seedfinder

New detector independent seedfinder implementation based on the ATLAS implementation. I tried to encapsulate parts that may be detector specific in tools. Please tell me where more comments are required. Templated on SpacePoint, returns a vector of vectors with results to avoid locking a single output container. To allow parallelization, the user calls createSeedsForRegion with an iterator, and for each of these regions a separate output container is filled. Less fine grained than per-spacepoint: ATLAS configuration would mean 260 parallelizable regions (independent of # of measurements).

Functionality to be added later: Returning an iterator that hides the looping over vector of vectors. Reducing bin size (increasing parallelism, reducing combinatorics), currently prevented by performance overhead from AnyGrid.

Find the delta to ATLAS Seeding