[FEATURE] Disable Dashboard and Dashboard API

Allows pools to disable the dashboard and dashboard API completely.
Useful if you are not running a master/load(/load/load) setup to deal
with frequent live queries.

Fixes #876 once merged.
[FIX] Show price/workers
[IMPROVED] Added balance checks post payouts

Fixes #904 once merged.
[UPDATE] Removed redundant calls
[ADDED] System load to dashboard call
[IMPROVED] Check system load, dashboard updates

This will suspend any dashboard updates if the system load exceeds a
configurable threshold. Graphs will not update until the system load is
again below the threshold.

See dist config for new option.

Should help those pools suffering from too many live update users.
[MERGE] Fixed merge conflict
[IMPROVED] Use static data first on dashboard
Update README.md

Removing some unused pools.
[UPDATE] Cache RPC getinfo calls
Merge branch 'next' of https://github.com/TheSerapher/php-mpos into next
[ADDED] getInfo output to wallet information

Adds some additional wallet infos to the wallet info page in the admin
panel. Specifically the errors output might be interesting for users not
checking their RPC regularly for mandatory updates.

Fixes #912 once merged.
Merge pull request #913 from TheSerapher/issue-912

[ADDED] getInfo output to wallet information
[FIX] No uptime status on empty result

Fixes #910 once merged
Merge pull request #914 from TheSerapher/issue-910

[FIX] No uptime status on empty result
[CHANGED] Do not send mail on uptime robot update

Do not send a mail notification in case the uptime robot updates are
failing.

Fixes #897 once merged.
Merge pull request #915 from TheSerapher/issue-897

[CHANGED] Do not send mail on uptime robot update
[IMPROVED] Lockout user on invalid pin/password

This will lock a user account if a password or PIN has been entered
wrong for multiple times in a row. When unlocking the account via admin
panel, both counters are reset so the user can log in again.

This should fix issues with brute force attacks to access user accounts.

Please see configuration dist file for new config options.
Please import SQL upgrade 007 to add new column to user accounts table.

Addresses #670 and should be merged once tested.
[ADDED] ACL to hide news post author

This will allow admins to hide the actual username/author from their newsposts.
Useful if you don't wish to give your admin account away or in case you
have no admin-only account.
[ADDED] Transaction summary to getuserstatus API

Fixes #917 once merged.