Add powercapping logic to use power_cpufreq

[PATCH 2/5] Add powercapping logic to make use of the power_cpufreq
 layout. The new logic allows the usage of only one of
 the existing layouts either power or power_cpufreq to
 take into account for the power adaptive scheduling. It
 considers the cpu frequency possibilities of the nodes
 as populated within the layouts along with the jobs'
 choices for allowed cpu frequencies for their
 execution. Based on the available power budget and the
 cluster's current maximum consumption it calculates if
 the job can be allocated and if yes with which allowed
 CPU frequency.