Fix for UI10 type fields for issue #1657

Css fix for displaying correctly uitype 10 fields in detail view, when opened for editing value.

See merge request !845

fix dates filter issues on #1666 and #1638

fix dates filter for every module, even reports.

See merge request !844

allow unlinking related items if you can edit the parent item fix #210

deleting a relationship should require edit access to the parent object (the one they are related to) not delete access to the target object. (because you are not deleting it, just disassociating it which is an edit to the parent object)

See merge request !70

Issue #1002 MainManager exception while fetching related items

Also, detecting sent emails to compare with current user email

See merge request !321

standalone #1639 mailconverter custom actions

With this modification it's possible to add custom actions to mail converter just like custom workflow function! New action would be displayed along with default actions.

Follow this example:
```
require_once('modules/Settings/MailConverter/handlers/MailScannerEntityMethodManager.inc');
$emm = new MailScannerEntityMethodManager($adb);
$moduleName='HelpDesk';
$methodName='createticketcustom';
$functionName='createticketcustom_helpdesk';
$functionPath='modules/yourmodule/yourmoduleHandler.php';
$emm->removeEntityMethod($moduleName, $methodName);
$emm->addEntityMethod($moduleName, $methodName, $functionPath, $functionName);

See merge request !838

Fixed query error impacting performances in inventory

This merge request is fixing and error in several queries impacting significantly performances if there are a big number of orders in the database.
Replaced:
vtiger_invoice_recurring_info.start_period = vtiger_salesorder.salesorderid
With:
vtiger_invoice_recurring_info.salesorderid = vtiger_salesorder.salesorderid

See merge request !842

mass_mail fix for #1559

fix for sending singularly mass emails from index view

See merge request !840

Price books popups fix

The pop up doesn't fill the values

See merge request !836

The pop up doesn't fill the values