Several warnings during Advanced Pack upgrade to 1.24.0

[Dmitry Danilson]

Hello!

Follow-up of https://github.com/espocrm/espocrm/issues/594.
I've encountered several warnings during Advanced Pack upgrade to 1.24.0.
EspoCRM version is 4.7.2.

[2017-07-17 04:06:19] Espo.WARNING: E_WARNING: Invalid argument supplied for foreach() {"code":2,"message":"Invalid argument supplied for foreach()","file":"/var/www/html/crm/application/Espo/Core/Utils/Metadata.php","line":249,"context":{"data":<here goes very big array of data>}} []
[2017-07-17 04:06:23] Espo.WARNING: E_WARNING: Invalid argument supplied for foreach() {"code":2,"message":"Invalid argument supplied for foreach()","file":"/var/www/html/crm/application/Espo/Core/Utils/Database/Orm/Converter.php","line":255,"context":{"entityName":"Workflow","entityMeta":{"serviceActions":{"Opportunity":{"OpportunityRecalculation":{"serviceName":"OpportunityRecalculation","methodName":"recalculateAction"}}}},"unmergedFields":["name"],"outputMeta":{"id":{"type":"id","dbType":"varchar"},"name":{"type":"varchar","notStorable":true},"deleted":{"type":"bool","default":false}}}} []
[2017-07-17 04:06:28] Espo.WARNING: E_WARNING: Invalid argument supplied for foreach() {"code":2,"message":"Invalid argument supplied for foreach()","file":"/var/www/html/crm/application/Espo/Core/Utils/Database/Orm/Converter.php","line":255,"context":{"entityName":"Workflow","entityMeta":{"serviceActions":{"Opportunity":{"OpportunityRecalculation":{"serviceName":"OpportunityRecalculation","methodName":"recalculateAction"}}}},"unmergedFields":["name"],"outputMeta":{"id":{"type":"id","dbType":"varchar"},"name":{"type":"varchar","notStorable":true},"deleted":{"type":"bool","default":false}}}} []
[2017-07-17 04:11:05] Espo.WARNING: E_WARNING: mkdir(): File exists {"code":2,"message":"mkdir(): File exists","file":"/var/www/html/crm/application/Espo/Core/Utils/File/Manager.php","line":396,"context":{"path":"data/cache/application","permission":"509","recursive":true,"fullPath":"data/cache/application","defaultPermissions":{"dir":"0775","file":"0664","user":33,"group":33}}} []
[2017-07-17 04:11:05] Espo.WARNING: E_WARNING: mkdir(): File exists {"code":2,"message":"mkdir(): File exists","file":"/var/www/html/crm/application/Espo/Core/Utils/File/Manager.php","line":396,"context":{"path":"data/cache/application","permission":"509","recursive":true,"fullPath":"data/cache/application","defaultPermissions":{"dir":"0775","file":"0664","user":33,"group":33}}} []