Cherry-pick the following commits from master to bump opkg in LEDE 17.01:b65dc04712opkg: switch to own fork to improve memory usage55ffc38004opkg: re-enable usign support19720a6f03opkg: fix handling conffiles in status lists9e4555f58dopkg: fix stray printf() (#551)ebf846b005opkg: mark as essential (FS#571)aedd5d5cb0opkg: fix several package installation bugs48ae44d033opkg: gracefully handle missing $PATH, fix build warnings1449b52f02opkg: backport upstream fixes, code cleanups Signed-off-by: Jo-Philipp Wich <jo@mein.io>