CSFML 2.6.0

Finally bringing CSFML inline with SFML 2.6! 🎉

• SFML feature implementations:
  • sfFont_setSmooth / sfFont_isSmooth (#186) by @dogunbound
  • sfPacket_getReadPosition (#186) by @dogunbound
  • sfBlendMin & sfBlendMax (#191) by @ChrisThrasher
  • sfFloatRect_getPosition/sfIntRect_getPosition & sfFloatRect_getSize/sfIntRect_getSize (#190) by @ChrisThrasher
  • Document MP3 support (#193) by @ChrisThrasher
  • Add directional arrow resize cursors (#194) by @ChrisThrasher
  • sfFont_getBoldKerning (#192) by @dogunbound
  • Add sf::Vulkan functions (#198, #212) by @ChrisThrasher & @eXpl0it3r
  • Add scancode support (#197) by @ChrisThrasher
  • sfRenderTexture_isSrgb / sfRenderWindow_isSrgb (#196) by @ChrisThrasher
  • sfImage_saveToMemory with sfBuffer (#205) by @kimci86
  • sf::WindowBase (#207) by @ChrisThrasher
• Various CI improvements (#186, #201, #204, #206, #214, #216, #224) by @dogunbound & @ChrisThrasher & @eXpl0it3r
• Use sf::err() for logging (#221) by @ChrisThrasher
• CSFML usage improvements (#189) by @tintou
• Add pkg-config support (#188) by @tintou
• Add and build example (#215) by @ChrisThrasher
• Enable and fix compiler warnings (#200, #219) by @ChrisThrasher & @kimci86
• Documentation fixes (#199, #203) by @kimci86 & @mgrojo
• Code clean ups (#218) by @ChrisThrasher

Thank you to everyone who contributed!