Enabling the saving of attachments

If there is no activity to view the attachment, it should be still possible to
save it. Therefore the canSave = false flag is wrong.

Change-Id: I3b6c19f9c99d99b20ccfa8d6bc9dae5a3eb24772
Merge branch 'cm-10.1' of git://github.com/CyanogenMod/android_packages_apps_Email into cm-10.1