triggers primary tree installation based on a mininet host ping a special ip address

when the mininet host pings "10.99.99.99" an ARP request is received at the controller at which point the primary trees are installed. a hack was needed:  to silence the ARP ping-ponging (infinite sometimes), we ignore all ARP requests (except those to a known multicast address) after the primary trees are installed
partially complete merger optimization algorithm

implemented (1) tagging all edges used by primary trees, (2) traversing all primary tree BFS to set up the implementation of the tagging rules
H6S10 topology files
H6S10 topology included.  new intilization

initialization sends a message to special IP address to trigger the installation of the primary trees
keep_tag, new_tag, and remove_tag indices created

created indices for keep_tag, new_tag, and remove_tag.  no tagging upstream.  have not yet used these indices to create flow entry rules
removed old deprecated functions from old way of installing multicast trees
refactored new_tag, remove_tag, new_tag
partially working creation of ofp rules.  still need to rewrite destination at the leaf nodes
Phase 1 of Merger implementation for primary trees is complete

works for primary trees only.  we are not tagging upstream yet.  tested for H6S10