* Updating common/lib
* Updating lib/csu
* Updating lib/libc
* Updating libexec/ld.elf_so
* Corrected test on __minix in featuretest to actually follow the
meaning of the comment.
* Cleaned up _REENTRANT-related defintions.
* Disabled -D_REENTRANT for libfetch
* Removing some unneeded __NBSD_LIBC defines and tests
Change-Id: Ic1394baef74d11b9f86b312f5ff4bbc3cbf72ce2
- add "edit" menu option, to edit menu commands before executing them;
- add "menu" boot command, to return to the menu from the prompt;
- provide more line editing features when getting input;
- fix a few potential buffer overflows as a side effect.