[IMPROVED] Unlock notification mails on auto-locks

* Added new token type: account_unlock
* Added update SQL File
* Updated base structure with new token type
* Added empty template
* Updated user class to send mail on failed passwords
* Added unlock account page to use tokens

Addresses #670
[ADDED] Account unlock mail on failed PIN
Update POOLS.md

fixed spelling :D
Merge pull request #1236 from PesiHUN/patch-1

Update POOLS.md
Update POOLS.md
Merge pull request #1239 from retal/patch-2

Update POOLS.md
Merge pull request #1213 from TheSerapher/issue-670-unlocks

[IMPROVED] Unlock notification mails on auto-locks
[INITIAL] Working version checks

* Check DB structure version, config file version and MPOS core version
* Added new Admin Dashboard to show this core information
* Cronjobs will be disabled if SQL files are not imported
 * SQL files must re-set the db_upgrade_required setting
* Cronjobs will disabled if config files are not updated
 * Simple config file update and version string update will fix this
* Added MPOS status overview
 * Cronjobs and Wallet information for now, others may be added later
* Added new navigation link for Admin Panel Dashboard
* Added new version file
 * Will require updates whenever DB or configs are updated
* Update SQL file that adds the DB_VERSION setting

This will address #1242 and already includes a huge chunk of changes
required to make this work.
[UPSTREAM] Upgraded smarty libraries

Fixes #1249 once merged.
Merge pull request #1250 from TheSerapher/issue-1249

[UPSTREAM] Upgraded smarty libraries
Update POOLS.md
Merge pull request #1254 from daygle/patch-2

Update POOLS.md
[FIX] Closing nocache tags

Fixes #1255 once merged.
Merge pull request #1259 from TheSerapher/issue-1255

[FIX] Closing nocache tags
[UPDATE] Check for upgrade later
Update README.md

Added 64bit as requirement if you want proper network hashrates.
[FIX] Caching issues with hybrid templates

* Create subfolders for cache/compiled files for themes

Fixes #1016 once merged.
[FIX] Empty / no template detection
    [UPDATE] Allow deletion of accounts

    Updated backend and theme to be able to deal with deleted accounts

    * Backends will skip any users that have no account_id associated with
      their shares
    * Updated round stats theme to show users as unknown if none can be found

    This will not fully address the issue of account deletion but at least
    wont break the system anymore.
Merge pull request #1264 from TheSerapher/issue-1016

[FIX] Caching issues with hybrid templates