KAZOO-1213: make adding/removing FreeSWITCH ndoes persistent for the current node
KAZOO-1213: allow setting of node (default or current node) for ecallmgr doc
KAZOO-1213: add {add,remove}_fs_node/2 to set whether to update default list of node's list

{add,remove}_fs_node(FSNode, AsDefault) where AsDefault is true/false, and updates the default list if true.
KAZOO-1213: update the sysconf set API handler
KAZOO-1213: remove Node from sysconf APIs, since its a default header
KAZOO-1213: flush local cache, and issue flush to sysconf whapps

also add more support for manipulating the default sysconf object
KAZOO-1213: ACL management APIs
KAZOO-1213: handle flush API reqs
KAZOO-1213: update tickies and whatnot
KAZOO-1213: add bindings for 'flush' and make key optional on flush
KAZOO-1213: formatting updates
KAZOO-1213: don't fetch acl config from default only, and remove the remove_* acl functions

We pull ACLs from the sip_auth db as well as the ecallmgr system_config doc, so
we can't just remove an ACL from the list.
KAZOO-1213: toggle whether to use the default or node-specific acl list
KAZOO_1213: allow listing from default or node specific ACL list
KAZOO-1213: filter out non-ecallmgr system_config doc ACLs
KAZOO-1213: formatting