This macro used to protect the declaration of the [vram] variable of
gint. This variable was short to keep drawing functions short but could
clutter the namespace.
That being said, it's even better to just [#define vram gint_vram] if
you need. This change renames the variable to [gint_vram], exposes it
whenever <gint/display.h> is included, and removes the GINT_NEED_VRAM
macro altogether.
Since Memallox's newlib port is currently unstable, gint has to
provide some standard functions on its own. Instead of a single
<gint/std.h> header, this commit makes a gint/std directory containing
headers under standard names.