Print::write(const uint8_t *buffer, size_t size) and Print::print(const
__FlashStringHelper *ifsh) would continue calling write(char) after a
failed write(char) this behavior would render returned count unuseable
see arduino/Arduino issue #3614
On later versions of avr-libc, prog_char is deprecated. In 0acebeeff4
the one occurence of prog_char was replaced by "char PROGMEM", which is
not entirely correct (PROGMEM is supposed to be an attribute on a
variable, not on a type, even though this is how things work in older
libc versions). However, in 1130fede3a a few new occurences of
prog_char are introduced, which break compilation on newer libc versions
again.
This commit changes all these pointer types to use the PGM_P macro from
<avr/pgmspace.h>. This macro is just "const char *" in newer libc
versions and "const prog_char *" in older versions, so it should always
work.
References #795
Made some helper class for files filtering.
platforms.txt now contains only one platform at a time.
Some cleanup in Compiler and AvrDudeUploader classes.
