v0.2.0

• Improvements in SCM <-> C argument conversion
  • simplified to GType + metadata (#31)
  • more type associations (#25)
    • enum and flags classes, plus an API for them (#33)
    • procedure wrappers for callbacks and closures
    • accessor wrapper for values
    • integer data types must be <integer>
    • float and double must be <real>
• Support generation of documentation
  • In-REPL documentation through guile-procedures.txt (#24)
  • Docbook XML (#23)
  • Add gtkdoc support through gi-gtkdoc (use guild to invoke)