include pytest.ini in MANIFEST.in

closes #454
Allow specifiying bid for master
run user script on node add
Work on options for number of workers per machine
Save the userdata_scripts used in tag
Wait on completion of user script
Revert changes to sentinel
Fix to user data scripts loading
Update services
Initial commit of SGEInstaller
on_add_node and on_remove_node for sgeinstaller
HACK fix for date parsing
added slots_per_host option to load_balance
allow disabling default plugin
Add master to queue with slots=0
hacks
handle ssl cert for VPC
removed hacks
Modifies the is_cluster_terminated check to include instances that belong to the placement group

It seems that when a instance is terminated in a VPC the security group is automatically removed
from the instance metadata causing the is_cluster_terminated to return a false positive.
The code will then continue and try to remove the placement group but time out since the
placement group cannot be removed with instances remaining.
more issues with VPC IPS