add introduction blurb for the SPF implementation
add introduction blurb for the SPF implementation

zioproto/olsrd-gsoc2012,diogomg/olsrd-binary-heap,duydb2/olsr,diogomg/olsrd,nolith/olsrd,ralisi/olsrd_cl_roam,nolith/olsrd,diogomg/olsrd,acinonyx/olsrd,sebkur/olsrd,tdz/olsrd,acinonyx/olsrd,ninuxorg/olsrd,brabander/olsr,ninuxorg/olsrd,zioproto/olsrd-gsoc2012,brabander/olsr,diogomg/olsrd,sauloqueiroz/incremental-spf,diogomg/olsrd,zioproto/olsrd-gsoc2012,sauloqueiroz/incremental-spf,duydb2/olsr,tdz/olsrd,duydb2/olsr,diogomg/olsrd-binary-heap,diogomg/olsrd-binary-heap,servalproject/olsr,diogomg/olsrd,ralisi/olsrd_cl_roam,cl4u2/olsrd-wot-pgp,servalproject/olsr,ralisi/olsrd_cl_roam,sebkur/olsrd,cholin/olsrd,diogomg/olsrd-binary-heap,diogomg/olsrd-binary-heap,servalproject/olsr,duydb2/olsr,cl4u2/olsrd-wot-pgp,cholin/olsrd,zioproto/olsrd-gsoc2012,duydb2/olsr,diogomg/olsrd,cl4u2/olsrd-wot-pgp,nolith/olsrd,cholin/olsrd,cl4u2/olsrd-wot-pgp,ninuxorg/olsrd,zioproto/olsrd,diogomg/olsrd-binary-heap,servalproject/olsr,zioproto/olsrd,tdz/olsrd,ninuxorg/olsrd,servalproject/olsr,cholin/olsrd,tdz/olsrd,sebkur/olsrd,acinonyx/olsrd,duydb2/olsr,ralisi/olsrd_cl_roam,sebkur/olsrd,sebkur/olsrd,nolith/olsrd,ninuxorg/olsrd,acinonyx/olsrd,servalproject/olsr,nolith/olsrd,brabander/olsr,diogomg/olsrd,cholin/olsrd,zioproto/olsrd,zioproto/olsrd-gsoc2012,duydb2/olsr,sauloqueiroz/incremental-spf,zioproto/olsrd,tdz/olsrd,zioproto/olsrd-gsoc2012,zioproto/olsrd,diogomg/olsrd-binary-heap,cl4u2/olsrd-wot-pgp,sebkur/olsrd,sauloqueiroz/incremental-spf,acinonyx/olsrd,duydb2/olsr,brabander/olsr