When no password is set (logged in via oauth), don't ask for password
when saving profile and ask for username when deleting account.

Embedded media like images and video can now individually be collapsed

A new preference "Collapse media by default" is also added, the default
is to not collapse media.

Since images are not always shown, "showImage" is also renamed to
"loadImage"

Closes #1187

Closes #2483

Moves change of password to profile;
Moves change of language to preferences;
Requires current password to change profile settings;

    If users language setting is different from default app language setting, front end app language should change to user's language once user login
2. Fix the wrong language display in the view of  accountProfile.

Add the ability to set the default language for new users.
Admin can set server default language in admin/General section.

Currently when you upload an image as an avatar, the "SELECT FILE" button disappears and you get another button to use the uploaded file. However, if you didn't like how the uploaded image looks you cannot upload another one. The work around is to reopen the avatar settings page, instead the upload button should stay there to allow the user to upload a different image.