Add standalone prescaler algorithm

This MR adds a standalone prescaler algorithm, decoupled from the line, which allows reconstruction algorithms to be masked if the lines using them are prescaled. It also change how the boolean expressions of the masks are simplified, since the sympy algorithm was too slow and giving up for expression of more than 8 variables.

The boolean simplication algorithm used here is from the library https://github.com/bastikr/boolean.py which is included here as a single python file. Alternatively, the pyeda library was added to the latest version of LCG but we cannot use it yet in Allen.

FYI @dovombru @cagapopo @samarian @raaij