Use correct include syntax

Angle brackets for external includes. Quotes for internal includes. The former is not critical but the latter is necessary in order to use the library bundled with a sketch, where Adafruit_PWMServoDriver.h will not be found in the include search path.

Author: per1234

Adafruit_PWMServoDriver.cpp

@@ -15,7 +15,7 @@
   BSD license, all text above must be included in any redistribution
  ****************************************************/
 
-#include <Adafruit_PWMServoDriver.h>
+#include "Adafruit_PWMServoDriver.h"
 #include <Wire.h>
 
 // Set to true to print some debug messages, or false to disable them.

Adafruit_PWMServoDriver.h

@@ -19,11 +19,11 @@
 #define _ADAFRUIT_PWMServoDriver_H
 
 #if ARDUINO >= 100
- #include "Arduino.h"
+ #include <Arduino.h>
 #else
- #include "WProgram.h"
+ #include <WProgram.h>
 #endif
-#include "Wire.h"
+#include <Wire.h>
 
 #define PCA9685_SUBADR1 0x2
 #define PCA9685_SUBADR2 0x3