add enum baudrates (#376)

* add enum baudrates

fixes perceived limitation of available baud rates https://github.com/Microsoft/pxt/issues/1752

* correct block comment

* comma correction and remove trailing space

That will teach me just to do cut and paste via github web interface :(

* without running pxt buildtarget

libs/core/_locales/core-strings.json

@@ -21,6 +21,15 @@
   "AnalogPin.P8|block": "P8 (write only)",
   "AnalogPin.P9|block": "P9 (write only)",
   "BaudRate.BaudRate115200|block": "115200",
+  "BaudRate.BaudRate1200|block": "1200",
+  "BaudRate.BaudRate14400|block": "14400",
+  "BaudRate.BaudRate19200|block": "19200",
+  "BaudRate.BaudRate2400|block": "2400",
+  "BaudRate.BaudRate28800|block": "28800",
+  "BaudRate.BaudRate300|block": "300",
+  "BaudRate.BaudRate38400|block": "38400",
+  "BaudRate.BaudRate4800|block": "4800",
+  "BaudRate.BaudRate57600|block": "57600",
   "BaudRate.BaudRate9600|block": "9600",
   "BeatFraction.Breve|block": "4",
   "BeatFraction.Double|block": "2",

libs/core/enums.d.ts

@@ -443,8 +443,26 @@ declare namespace led {
     declare enum BaudRate {
     //% block=115200
     BaudRate115200 = 115200,
+    //% block=57600
+    BaudRate57600 = 57600,
+    //% block=38400
+    BaudRate38400 = 38400,
+    //% block=28800
+    BaudRate28800 = 28800,
+    //% block=19200
+    BaudRate19200 = 19200,
+    //% block=14400
+    BaudRate14400 = 14400,
     //% block=9600
     BaudRate9600 = 9600,
+    //% block=4800
+    BaudRate4800 = 4800,
+    //% block=2400
+    BaudRate2400 = 2400,
+    //% block=1200
+    BaudRate1200 = 1200,
+    //% block=300
+    BaudRate300 = 300,
     }
 
 

libs/core/serial.cpp

@@ -15,8 +15,26 @@ enum SerialPin {
 enum BaudRate {
   //% block=115200
   BaudRate115200 = 115200,
+  //% block=57600
+  BaudRate57600 = 57600,
+  //% block=38400
+  BaudRate38400 = 38400,
+  //% block=28800
+  BaudRate28800 = 28800,
+  //% block=19200
+  BaudRate19200 = 19200,
+  //% block=14400
+  BaudRate14400 = 14400,
   //% block=9600
-  BaudRate9600 = 9600
+  BaudRate9600 = 9600,
+  //% block=4800
+  BaudRate4800 = 4800,
+  //% block=2400
+  BaudRate2400 = 2400,
+  //% block=1200
+  BaudRate1200 = 1200,
+  //% block=300
+  BaudRate300 = 300
 };
 
 enum Delimiters {