basic skeleton to work with sc_notify

sc_notify() lets every proc know which procs wants to send him something
Merge branch 'master' into sendMessages

Conflicts:
	particleChase.c
change upper limit since i is looping over miniQuads
hello p4estindent
precise comment and move iterator init to for loop
ADD init function to handle p4est specific details
alloc particle send lists
stuff
update iterator
comment update
test with 4 particles in a 4 times 4 square
free memory
move particle to send list instead of freeing it here
update comment
inserting all particles on proc 0 and spread them
indent..
current status -> init particles_to lists by hand
update comments and indentation
resolve receivers after all particles are handled
sorting is not needed due to new calculation of receivers array