[FIX] updated styles, typos and colors
[FIX] typo
[FIX] Remove static table references
[ADDED] Admin Pool Newsletter

* Added throttle option to swiftmailer for SMTP limiting
* Added newsletter page for admin panel
* Added newsletter mail template (simple one for now)
* Added new global configuration option
* Added default notification setting system in notification class
* Added global pool newsletter enable/disable switch in admin settings

Fixes #2087 once merged.
rebase
[FIX] Skip locked accounts
Merge pull request #2085 from barrybingo/development

[FIX] Remove static table references
rollback
[UPDATE] style fixes
[FIX] Merge conflict
Merge branch 'development' of https://github.com/MPOS/php-mpos into development
[FIX] Logic error for notification setting
[FIX] Return defaults with no settings at all
Merge pull request #2088 from MPOS/pool-newsletter

Pool newsletter