fix(): fix(service,start): missing folder PID : /var/run/mast/*

due to invalid quoting
# wrong !
"$(throttle) ${channel[@]}" # wrong !
# GOOD !
$(throttle) "${channel[@]}" # throttle is not quoted


fixes #46
fix(service,stdout): correct message to reflect task
feat(mk): edit sudoers to allow 'mast' user and 'www-data' group
fix(mk,add-host): permissions when creating tunnel

Rollback part of commit 2d94cbc736:
* fix(add-channel): solve permissions issues (log files, config)

closes #49
fix(service,install,check-privileges): update group variable

fixes #50
doc(requirements): require a 'coaxis' user as defined by `REMOTE_USER`
refactor(mk): rename 'install-infra' → 'requirements', remove setup-infra
doc(links): update due to previous commit/refachor

rename 'install-infra' → 'requirements', remove setup-infra
fix(service,start): su: invalid option -- 'd' on trickle (refactor)

Refactor to use 'sudo'

closes #48
related #46