Update bmv2.py to run stratum_bmv2 plus various improvements

Also added alias to quickly run mininet with stratum in cell machines
and p4vm

Change-Id: Id10bf8f3de4fe14d77b5efe47b6129a8a28b5a89
diff --git a/tools/dev/bash_profile b/tools/dev/bash_profile
index 06d3495..8212dbf 100644
--- a/tools/dev/bash_profile
+++ b/tools/dev/bash_profile
@@ -343,4 +343,5 @@
 alias uktopo='onos-netcfg $OCI $ONOS_ROOT/tools/test/topos/uk-cfg.json'
 
 # Mininet command that uses BMv2 instead of OVS
-alias mn-p4='sudo -E mn --custom $BMV2_MN_PY --switch onosbmv2 --controller remote,ip=$OC1'
+alias mn-bmv2='sudo -E mn --custom $BMV2_MN_PY --switch onosbmv2 --controller remote,ip=$OC1'
+alias mn-stratum='sudo -E mn --custom $BMV2_MN_PY --switch stratum --controller remote,ip=$OC1'