new code for lua protected calls in lua_kernel_base

In initial commit of the new lua kernels, I introduced a problem
by trying to use luaW_pcall and lua_pcall interchangeably via
polymorphism. This doesn't work because their return types don't
match, and it's alot of work to change luaW_pcall syntax. Besides
this there's no reason we can't use the custom error handler
everywhere.

This commits adds protected_call and load_string functions to lua
kernel base. These are an intended replacement for luaW_pcall,
and replace the "run" function. They do better error reporting
and allow to specify an error handler.
use setfuncs instead of register, so we can do partial define
move some callbacks (gettext, file ops) to lua kernel base