Expert Benchmark: Properly resetting y-axis of sparse bench.
Corrected number of tests in progress bar.

Used to stop at "95 of 99" because number of tests wasn't calculated correctly.
Defaults: Changed BLAS3 settings to 2048 max, reduced vector size to 5Mio.

Otherwise we likely run into memory allocation issues on weaker hardware.
Added info-dialog after MatrixMarket file is downloaded.

Tells the user to go to the advanced tab and run the benchmark.
Better than no feedback from the GUI at all.