Use constants from `TRestPhysics`

[juanangp]

Migrate to TRestPhysics constants, currently wimplib has different units than REST, so there are two options:

• Migrate to REST units
• Define wimplib units based on REST units.

Related to #1

[jgalan]

It is a matter of units, or it is a matter of constants? It is true than in TRestPhysics there is a units problem because we are not using there the default units as defined by TRestSystemOfUnits.

[juanangp]

I think it is a matter of units because e.g. we use km/s for the speed and GeV for the WIMP mass.

On the other hand, I think the constants in general should use RESTUnits