added vim ~ file to .gitignore
reverted uart.c to original
no longer building against the host's include path
made _Reset global to eliminate linker warning.
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
Merge branch 'data_structures' of https://github.com/rellermeyer/course_os into test
	new file:   kernel/data_structures/stack.c
	new file:   kernel/include/stack.h
	modified:   kernel/memory/mem_alloc.c