make allocation strategy pluggable
make configuration file can be passed from client side
I disabled the client to check number of process (-np) in client, because now we don't have a mpirun parameter parsing, we cannot gurantee a argv like -np is NOT used by a user's program, it will affected log fetcher, I disabled it also
add parameter support for user-policy-based allocation strategy in client
add code to set configuration of user driven policy in client
add file forgot in last commit :-/
add implementation of host expression expander, need add test, ckpt
finished user policy based allocation strategy impl, ckpt
add implementation of user policy driven allocation strategy, make it usable in local node
add missing license from original pbc repository