Change default mount options for NTFS drives to prevent execution permission by default

[ongun-kanat]

udisks2 and the client applications mount NTFS drives with 0777 permissions by default including the external drives. The external USBs are used as common attack vectors and can carry different exploits. By denying execution permissions by default on files udisks2 can add a layer of security. ntfs-3g has two different options for files and directories changing the default permission as fmask=0111 should be enough.

This behavior can be improved by different sets of default rules for internal and external drives if #609 is implemented in the future.

[tbzatek]

This can be now configured system-wide individually. Please check the docs and examples for the instructions.

[ongun-kanat]

Yes! I have been waiting for this feature for so long! Thank you for your efforts.