3.0.3

• #700: Digest Auth fails on HEAD requests.
• Fixed example files to no longer use now-deprecated realm argument.
• The zip release ships with sabre/vobject 3.4.6,
  sabre/http 4.0.0, sabre/event 2.0.2,
  sabre/uri 1.0.1 and sabre/xml 1.1.0.