Move information re: SoftwareSerial pins to table

Previously, the information about which pins could be used with the SoftwareSerial library was documented in prose form.

Although reasonable in the context of only needing to cover a few boards as was the case at the time the documentation
was established, this approach does not scale as it is necessary to add information for more boards over time. For this
reason, the information is migrated to a table in preparation for addition of the missing documentation for the newer
boards.

Author: per1234

content/learn/07.built-in-libraries/04.software-serial/software-serial.md

@@ -21,13 +21,19 @@ SoftwareSerial library has the following known limitations:
 
 * It cannot transmit and receive data at the same time.
 * If using multiple software serial ports, only one can receive data at a time.
-* Not all pins on the Mega and Mega 2560 boards support change interrupts, so only the following can be used for RX: 10, 11, 12, 13, 14, 15, 50, 51, 52, 53, A8 (62), A9 (63), A10 (64), A11 (65), A12 (66), A13 (67), A14 (68), A15 (69).
-Not all pins on the Leonardo and Micro boards support change interrupts, so only the following can be used for RX: 8, 9, 10, 11, 14 (MISO), 15 (SCK), 16 (MOSI).
-* On Arduino or Genuino 101 boards the current maximum RX speed is 57600bps. 
-* On Arduino or Genuino 101 boards RX doesn't work on digital pin 13.
+* On some boards, not all pins can be used. See the "**Supported Pins**" table below for details.
+* On Arduino or Genuino 101 boards the current maximum RX speed is 57600bps.
 
 If your project requires simultaneous data flows, see Paul Stoffregen's [AltSoftSerial library](https://www.pjrc.com/teensy/td_libs_AltSoftSerial.html).
 
+### Supported Pins
+
+| Board                    | RX                                           | TX  |
+| ------------------------ | -------------------------------------------- | --- |
+| 101                      | 0-12, 14 (A0) - 19 (A5)                      |     |
+| Leonardo<br />Micro      | 8, 9, 10, 11, 14 (MISO), 15 (SCK), 16 (MOSI) | Any |
+| Mega<br />Mega 2560 Rev3 | 10-15, 50-53, A8 (62)-A15 (69)               | Any |
+
 ## Examples
 
 * [SoftwareSerial example](/tutorials/communication/SoftwareSerialExample): sometimes one serial port just isn't enough!