Add uudecode/uuencode.

Some firmware flashing scripts rely on sharutils, which rely on
uudecode/uuencode. Since we're several decades too late to expect
anyone to update sharutils to use base64 instead, and POSIX
includes uudecode/uuencode, let's just support them.

Bug: http://b/31913440
Test: manual
Change-Id: Ia3893de08abfe5b8a8f58349bd298b912fa99e6a
4 files changed