This commit moves all first-party code developed for this project from lib/
to shared/, so that lib/ now only contains third-party code.
The following directories are moved as-is from lib to shared:
lib/libc -> shared/libc
lib/memzip -> shared/memzip
lib/netutils -> shared/netutils
lib/timeutils -> shared/timeutils
lib/upytesthelper -> shared/upytesthelper
All files in lib/embed/ have been moved to shared/libc/.
lib/mp-readline has been moved to shared/readline.
lib/utils has been moved to shared/runtime, with the exception of
lib/utils/printf.c which has been moved to shared/libc/printf.c.
Signed-off-by: Damien George <damien@micropython.org>
