Added compatibity for 1.5 libraries layout on IDE 1.0.x

See #1765
Update README.md

also make ToDo a link
Merge pull request #1958 from Ramoonus/patch-1

Update README.md
Merge branch 'master' into ide-1.5.x

Conflicts:
	app/src/processing/app/Sketch.java
	app/src/processing/app/debug/Compiler.java
Merge remote-tracking branch 'arduino/master' into ide-1.5.x
Fix typo in SerialEvent3 handling

In commit 0e97bcb (Put each HardwareSerial instance in its own .cpp
file), the serial event handling was changed. This was probably a
copy-paste typo.

The effect of this bug was that SerialEvent3 would not run, unless
SerialEvent2 was defined, but also that if SerialEvent2 is defined but
SerialEvent3 is not, this could cause a reset (call to NULL pointer).

This closes #1967, thanks to Peter Olson for finding the bug and fix.
Merge pull request #1968 from matthijskooijman/ide-1.5.x-hwserial-typo

Fix typo in SerialEvent3 handling
Spacebrew update
Merge branch 'ide-1.5.x' into ide-1.5.x-avr-toolchain-gcc-4.8.1