Merge branch 'base'

Fix voting reward calculation

- Do not decrease total voting amount when a P-Rep receives a turn skipping penalty

Merge branch 'base' into master

Merge pull request icon-project#85 from icon-project/bugfix/set-slash…

…ing-rate-to-zero

Set SlashingRate to 0 at revision 17

Fix ICX issue and regulate module

Consolidate codes for signature change of ServiceManager

Merge branch 'base' into master

Fix problem in transaction pool candidate logic

Merge remote-tracking branch 'origin/base'

Merge branch 'base' into github-master