(^) eliminate app<=>os dependencies (make them sys_calls)
    (^) ceu_org_init => ceu_sys_org_init
    (^) ceu_go => ceu_sys_go
    (^) ceu_wclocks_* => template.c
(*) AVR dependent
(^) sub => string.gsub
(^) CEU_APP_ADDR for LPM instructions
(^) ceu_malloc/ceu_free => ceu_sys_
(+) app->pid
(+) dynamically load app from flash