Online-QA module for STS raw digis

The module is represented with the class cbm::algo::sts::DigiQa (file StsDigiQa.h). On this iteration the following distributions are added: digi vs. channel vs. address, digi vs. charge vs. address, and digi vs. channel vs. charge vs. address.

Modification to histogram server:

• bugfix: the histogram server does not crash any more, if the canvas has more pads, then the corresponding canvas config
• possibility to save canvases into subdirectories was added

NOTE: this merge request should be merged after the !1689 (merged)