added -D__PROG_TYPES_COMPAT__ to the avr-g++ compiler flags

this results in just a deprecated warning rather than an error
when using libraries (e.g. jeelib) that still use prog_XXX types

this is how the IDE does it, and means that libraries don't have to
add the #define __PROG_TYPES_COMPAT__ line

Reference: http://www.nongnu.org/avr-libc/user-manual/group__avr__pgmspace.html

Arduino.mk

@@ -785,7 +785,7 @@ else
 endif
 
 # Using += instead of =, so that CPPFLAGS can be set per sketch level
-CPPFLAGS      += -$(MCU_FLAG_NAME)=$(MCU) -DF_CPU=$(F_CPU) -DARDUINO=$(ARDUINO_VERSION) \
+CPPFLAGS      += -$(MCU_FLAG_NAME)=$(MCU) -DF_CPU=$(F_CPU) -DARDUINO=$(ARDUINO_VERSION) -D__PROG_TYPES_COMPAT__ \
         -I. -I$(ARDUINO_CORE_PATH) -I$(ARDUINO_VAR_PATH)/$(VARIANT) \
         $(SYS_INCLUDES) $(USER_INCLUDES) -Wall -ffunction-sections \
         -fdata-sections

README.md

@@ -122,7 +122,7 @@ It is possible to use [`colorgcc`](https://github.com/colorgcc/colorgcc) with th
 
 ## Versioning
 
-The current version of the makefile is `1.3.1`. You can find the full history in the [HISTORY.md](HISTORY.md) file
+The current version of the makefile is `1.3.2`. You can find the full history in the [HISTORY.md](HISTORY.md) file
 
 This project adheres to Semantic [Versioning 2.0](http://semver.org/).