procutil: move mainfrozen() to new resourceutil.py The i18n module practically depends on procutil for mainfrozen() but since procutil depends on i18n, it would be a circular dependency if i18n depended directly on procutil. The cycle is currently resolved by having the higher-level util module calculate the "datapath" and inject it into i18n. Extracting mainfrozen() to a new module lets us clean up the dependencies. Differential Revision: https://phab.mercurial-scm.org/D7433