fixed warnings on materials at SIM step

Minor clean-up on materials:

1) Material Quartz was defined in the main material list with density 2.64 and in forward materials list with the density 2.2, this is HF specific material.  To remove the warning the last is renamed to QuartzF.

2) Heavy Boron Concrete definition had a minor problem: sum of mass fractions for components was not exact 1.0. The mass fraction of the first (largest) component is slightly increased.

3) In trackermaterial.xml there were number of hidden symbols

Overall this modifications should not affect any results.