Fixing efficiency in [DetectorHistogrammer] when sensor excess is present

Added a function to check whether a given position is within the pixel grid. Updated efficiency in [DetectorHistogrammer] using this.

Previously, the efficiency would be lower when an excess was present, as particles hitting the excess were counted as "particles that should have created a cluster", when they shouldn't and couldn't.

I did some tests, just a simple diode with 2500 µm excess and with 0 µm excess. In-pixel efficiency before, with excess:

Without excess:

After this MR, with excess:

Without excess:

There is still a difference, which stems from the track_resolution parameter (defaults to 2x2 µm). The in-pixel efficiency with excess and with track_resolution set to 0 0 (after this MR):

The excess reduces efficiency at sensor edges when there is a non-zero track resolution, as some of the hits in the excess will then still be considered as "should produce a cluster". This is quite clear in the efficiency of the full sensor (10x10 pixels); the efficiency drop is at the edges of the edge pixels.