icarus.py: Use Launcher instead of calling subprocess directly
modelsim.py: Clean up and remove exit(1)
remove utils/launch and replace launch with Laucher in quartus.py
add module sections.py to Makefile.am
coremanager: allow sub-directories in cores/systems

With this new features, we can have multiples sub-directories
in systems and cores directories. For example:

|
|-- de1
|   |-- de1
|   |-- de1-blink
|   `-- de1-eco32

This allows systems to be grouped under board name.

Signed-off-by: Franck Jullien <franck.jullien@gmail.com>