Add support for removing profile picture

[Mstrodl]

Right now there's no way that I could see in the web UI for removing your profile picture. I want to remove my photo so I can use my gravatar:

profiles/profiles/ldap.py

Lines 419 to 430 in d59c881

	# Return stored Image
	if image:
	return image, 200, {'Content-Type': 'image/jpeg', 'Cache-Control': 'max-age=31536000'}
	# Get Gravatar
	url = get_gravatar(uid)
	try:
	with urllib.request.urlopen(url) as gravatar:
	if gravatar.getcode() == 200:
	return redirect(url, code=302)
	except urllib.error.HTTPError:
	pass

[Mstrodl]

What I ended up doing: ipa user-mod mstrodl --setattr=jpegPhoto=