v2.7.0 - Early-Late Rules

#38

• uses older iptables 1.6.2 from alpine:3.8
• set ipvs-ignore-node-cordon = false by default.
• add option to skip ipvs-master node (only when running on director)
• convert the -d and -a on a weight change to -e.
• generate 2 sets of rules (early, late) to allow worker nodes to keep up
• speed up conversion of -d/-a to -e .
• order: (-d and some -e), -D, -A, (-a and some -e)
• Reformat source / rename functions.
• ipvs-ignore-node-cordon default is now True
• SKIP_MASTER_NODE=N by default

Example:
Current New Rules generated: 0014-newrules
-d -t 10.131.153.120:4002 -r 10.131.153.76:4002
-a -t 10.131.153.120:4002 -r 10.131.153.76:4002 -i -w 0

New Rule Generated instead: 0014-newrulesEarly.test
e -t 10.131.153.120:4002 -r 10.131.153.76:4002 -i -w 0

ENV-VAR:
--set-env=RAVEL_EARLYLATE=Y # generate 2 sets of rules instead of one.
--set-env=RAVEL_LOGRULE=N # logs curent/generated/rules in /tmp/ each time new rules are needed.
--set-env=SKIP_MASTER_NODE=N # skip ipvs-master node if running ipvs-master.