largefiles: remove 1.9 compat code

merge with i18n

i18n-pt_BR: synchronized with ab341fbb05b1

i18n-pt_BR: msgmerge with ab341fbb05b1

bisect: add i18n contexts

import: add i18n context

largefiles: fix some badly named function parameters overrides.py contains several functions that temporarily override scmutil.match(), which always takes a changectx object as the first parameter. But these overrides name that parameter either 'repo' or 'ctxorrepo', which is misleading. So rename them to 'ctx' and remove the special type-sensitive handling of the one called 'ctxorrepo'.

largefiles: tidy imports - no need to defensively import scmutil - remove duplicate - unwrap non-long line