Improvement: Extend LaunchManager to support runmask for 64 cores

[NicolasFussberger]

Currently, the launch manager only supports setting affinity for up to 32 cores.
As a result, every process started by launch manager can run on max 32 cores.
This shall be extended to support systems with up to 64 cores.

For details see discussions in #113

Take note about this caveat when bitshifting by more than 32 bits: #113 (comment)