lib.ptree: add acquire_cpu worker option
lib.ptree: add acquire_cpu worker option

defaults to true

snabbco/snabb,snabbco/snabb,snabbco/snabb,snabbco/snabb,snabbco/snabb,eugeneia/snabb,snabbco/snabb,eugeneia/snabb,snabbco/snabb,snabbco/snabb,eugeneia/snabb,eugeneia/snabb,eugeneia/snabb,eugeneia/snabb,eugeneia/snabb,eugeneia/snabb