Appveyor is not used for Mac builds, but for the automated Windows build.
- Extensive code cleanup (Erwin Janssen)
- Removal of libgd source - use vanilla libgd from separate install
- Windows builds (Erwin Janssen)
- - Appveyor CI for Mac builds (Erwin Janssen)
+ - Appveyor CI for automated Windows build testing (Erwin Janssen)
- Travis CI for Fedora/Centos builds (Erwin Janssen)
- Added JSON output format, -Tjson (Emden Gansner)
- New curved arrowhead, cylinder node shape.