Several ports use identical code for the 1-argument form of the builtin
help function. Move this code to a library function to allow easier
re-use by ports.
A port which uses lib/utils/pyexec.c but which does not enable garbage
collection should not need to implement the gc_collect function.
This patch also moves the gc_collect call to after printing the qstr
info. Since qstrs cannot be collected it should not make any difference
to the printed statistics.
The config variable MICROPY_MODULE_FROZEN is now made of two separate
parts: MICROPY_MODULE_FROZEN_STR and MICROPY_MODULE_FROZEN_MPY. This
allows to have none, either or both of frozen strings and frozen mpy
files (aka frozen bytecode).
Before this change, if REPL blocked executing some code, it was possible
to still input new statememts and excuting them, all leading to weird,
and portentially dangerous interaction.
TODO: Current implementation may have issues processing input accumulated
while REPL was blocked.
This is a convenience function similar to pyexec_file. It should be used
instead of raw mp_parse_compile_execute because the latter does not catch
and report exceptions.
In other words, unix port now uses overriden printf(), instead of using
libc's. This should remove almost all dependency on libc stdio (which
is bloated).
