Angled-brackets vs. quotes in #include directives

[Christopher Collins]

Hello all,

We've been a bit inconsistent with our use of angled-brackets vs. quotes
in #include directives.  There is a simple rule for this one: use
quotes for user headers; angled-brackets for headers supplied by the
implementation.  "Implementation" is a technical term meaning the
combination of compiler, standard library, linker, assembler, etc.

In other words,

GOOD:

    #include <stdio.h>
    #include <assert.h>
    #include "os/os.h"

BAD:

    #include <stdio.h>
    #include <assert.h>
    #include <os/os.h>

BAD:

    #include "stdio.h"
    #include "assert.h"
    #include "os/os.h"

Thanks,
Chris