larsrh/libisabelle: libisabelle 0.8.0

Major changes

• experimental support for Isabelle devel versions (0165472, 510beb4)
  • Platform moved from libisabelle-setup to libisabelle
  • Version is now split into Stable and Devel
  • GenericEnvironment is a new subclass of Environment that can be instantiated without classloading; only supports Isabelle tool invocations (e.g. build, jedit)

• CLI and test logging by scalog (43922d6)
• treat empty entries in file list (.libisabelle/.files) correctly (8898c0e)
• internal ExitTrap exception (used for control flow) is not printed anymore (0404c13)
• various dependency bumps (453a5e4, d013d66, 8946a7d,
• Isabelle2016-1 is identified correctly (6456157)
• changing (i.e. SNAPSHOT) artifacts are fetched again after TTL has expired (d1130d4)