New Timer Pin Tables

see also 
- https://www.robotshop.com/community/forum/t/arduino-101-timers-and-interrupts/13072
- http://www.arduino.cc/en/Tutorial/SecretsOfArduinoPWM
- http://sobisource.com/arduino-mega-pwm-pin-and-frequency-timer-control/

Fix release notes
add notice of being included in Arduino library manager

README.md

@@ -155,6 +155,8 @@ get reliable current measurements.  If `analogWrite` uses a frequency of 490&nbs
 
 Version History
 ---------------
+-   2019-03-28 Now officially in the Arduino Library Manager
+-   3.0.2-dualshields (2018-12-02): Fix default pins for motor 2 _CS4
 -   3.0.1-dualshields (2018-06-14): Fix Semver naming for Arduino Library Manager
 -   3.0.0.dualshields (2018-05-12): Allow PWM remapping (use analogWrite if PWM pins remapped). Follows PWM remapping changes in source library pololu/dual-vnh5019-motor-shield, possibly backwards compatable change to allow use with old versions of the Arduino IDE 
 -   2.0.0.dualshields (2016-08-20): Updated library to work with the Arduino Library Manager
@@ -216,12 +218,42 @@ well, you would add the capacitor between M2CS and GND.
 -   The Uno has 3 Timers and 6 PWM output pins 3, 5, 6, 9, 10, and 11
     -   timer 0 —– Pins 5, 6 (time functions like millis(), and delay() )
     -   timer 1 —– Pins 9, 10 (servo library)
-    -   timer 2 —– Pins 11, 3
+    -   timer 2 —– Pins 11, 3 (tone(), notone() functions)
+
+| Uno Timer | Timer output OCRnx | Timer bit mode | PWM pin output |     Conflicts    |
+|:---------:|:------------------:|:--------------:|:--------------:|:----------------:|
+|  Timer 1  |        OCR1A       |     16 bit     |        9       |   servo library  |
+|  Timer 1  |        OCR1B       |     16 bit     |       10       |   servo library  |
+|  Timer 2  |        OCR2A       |      8 bit     |       11       | tone(), notone(), MOSI/SPI |
+|  Timer 2  |        OCR2B       |      8 bit     |        3       | tone(), notone() |
+
 -   The Arduino Mega has 6 timers and 15 PWM outputs pins 2 to 13 and 44 to 46
     -   timer 0 —– pin 4, 13 (time functions like millis(), and delay() )
     -   timer 1 —– pin 11, 12
     -   timer 2 —– pin 9, 10 (tone(), notone() functions)
     -   timer 3 —– pin 2, 3, 5
     -   timer 4 —– pin 6, 7, 8
     -   timer 5 —– pin 44, 45, 46 (servo library)
+
+| Mega Timer | Timer output OCRnx | Timer bit mode | PWM pin output |     Conflicts    |
+|:----------:|:------------------:|:-------------:|:--------------:|:----------------:|
+|   Timer 1  |        OCR1A       |     16 bit    |       11       |         -        |
+|   Timer 1  |        OCR1B       |     16 bit    |       12       |         -        |
+|   Timer 2  |        OCR2A       |     8 bit     |       10       | tone(), notone() |
+|   Timer 2  |        OCR2B       |     8 bit     |        9       | tone(), notone() |
+|   Timer 3  |        OCR3A       |     16 bit    |        5       |         -        |
+|   Timer 3  |        OCR3B       |     16 bit    |        2       |         -        |
+|   Timer 3  |        OCR3C       |     16 bit    |        3       |         -        |
+|   Timer 4  |        OCR4A       |     16 bit    |        6       |         -        |
+|   Timer 4  |        OCR4B       |     16 bit    |        7       |         -        |
+|   Timer 4  |        OCR4C       |     16 bit    |        8       |         -        |
+|   Timer 5  |        OCR5A       |     16 bit    |       46       | servo library    |
+|   Timer 5  |        OCR5B       |     16 bit    |       45       | servo library    |
+|   Timer 5  |        OCR5C       |     16 bit    |       44       | servo library    |
+
+-   The Arduino Leonardo has 4 timers and 7 PWM outputs 
+    -   timer 0 —– Pins 3, 11 (time functions like millis(), and delay() )
+    -   timer 1 —– Pins 9, 10 (servo library)
+    -   timer 3 —– pin 5
+    -   timer 4 —– pin 6,13
 -   [You can manually implement a sudo PWM on any digital pin by repeatedly turning the pin on and off for the desired times](http://www.arduino.cc/en/Tutorial/SecretsOfArduinoPWM)