Added User Print - A "light" console out option (#8)

User print disables the normal print messages in the body of QMK/TMK
code and is meant as a lightweight alternative to NOPRINT. Use it when
you only want to do a spot of debugging but lack flash resources for
allowing all of the codebase to print (and store their wasteful
strings).

keyboards/planck/keymaps/pvc/config.h

@@ -68,10 +68,18 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
 /* disable debug print */
-//#define NO_DEBUG
+#ifndef NO_DEBUG
+#  define NO_DEBUG
+#endif
 
 /* disable print */
-//#define NO_PRINT
+// #ifndef NO_PRINT
+// #  define NO_PRINT
+// #endif
+
+/* Only print user print statements */
+#define USER_PRINT
+
 
 /* disable action features */
 //#define NO_ACTION_LAYER