hello-2-properties: fix small error in exercise instructions

Signed-off-by: Steven Bellens <steven.bellens@mech.kuleuven.be>
rtt-exercises: update OCL and RTT hints to ../install

Signed-off-by: Steven Bellens <u0063509@pma-09-040.mech.kuleuven.be>
Merge remote-tracking branch 'origin/rtt-2.0-examples' into rtt-2.0-examples
hello-6: generate component instead of executable.

Signed-off-by: Peter Soetens <peter@thesourceworks.com>