Merge pull request #18 from jrcutler/master

Make WIDTH & HEIGHT const

Adafruit_GFX.cpp

@@ -39,9 +39,11 @@ POSSIBILITY OF SUCH DAMAGE.
  #define pgm_read_byte(addr) (*(const unsigned char *)(addr))
 #endif
 
-Adafruit_GFX::Adafruit_GFX(int16_t w, int16_t h) {
-  _width    = WIDTH       = w;
-  _height   = HEIGHT      = h;
+Adafruit_GFX::Adafruit_GFX(int16_t w, int16_t h):
+  WIDTH(w), HEIGHT(h)
+{
+  _width    = WIDTH;
+  _height   = HEIGHT;
   rotation  = 0;
   cursor_y  = cursor_x    = 0;
   textsize  = 1;

Adafruit_GFX.h

@@ -70,8 +70,9 @@ class Adafruit_GFX : public Print {
   uint8_t getRotation(void);
 
  protected:
+  const int16_t
+    WIDTH, HEIGHT;   // This is the 'raw' display w/h - never changes
   int16_t
-    WIDTH, HEIGHT,   // This is the 'raw' display w/h - never changes
     _width, _height, // Display w/h as modified by current rotation
     cursor_x, cursor_y;
   uint16_t