included global_defs.h into course_os.img
updating dev with master
update with master
merged printf function from klibc
merged mmap.h file to consolidate PIC addresses (and some useful macros)
Added minimal locking
created a static buffer array
Added contributors
fixed merges; implemented buffer
Fixed dupes from merge
Fixed merge conflicts from uart branch
Merge branch 'dev' of https://github.com/rellermeyer/course_os into dev
no longer building against the host's include path
made _Reset global to eliminate linker warning.
Added print_char_uart0 as requested in note
added an initial userland with a stripped-down libc that barely does more than attempting a printf
Merge branch 'dev' of https://github.com/rellermeyer/course_os into dev

Conflicts:
	.gitignore
	kernel/uart.c
Fix compilation flag to work with inline assembly
uart.c cleanup