Color in the console

Allow each gui_print command to specify a color
Change LOGERR to use the error color
Theme should specify colors for error, warning, and highlight

Change-Id: Ie8ece34111f604e25fcb79e5b731cd4e61038ff9
diff --git a/gui/gui.h b/gui/gui.h
index 10bf6ce..a927cf3 100644
--- a/gui/gui.h
+++ b/gui/gui.h
@@ -25,6 +25,7 @@
 int gui_start();
 int gui_startPage(const char* page_name);
 void gui_print(const char *fmt, ...);
+void gui_print_color(const char *color, const char *fmt, ...);
 
 #endif  // _GUI_HEADER