1.18.4

This release contains small fixes and improvements:

• Flag parameters (that allow bitwise combinations) are now Set<> parameters. This impacts PDFOutlineFlags and FTSynthesize.
• Fixed the function descriptors of cairo_text_extents and cairo_glyph_extents
• Small Javadoc fixes
• Dependency upgrades

Full Changelog: 1.18.3...1.18.4