alpha.v3

Third alpha release!

Main changes:

• optimization to use less components on tilemap (#52)
• display the portals on tilemap (#53)
• add new asset image on upload rom modal! Thank to @Kniksisk (#50)
• add icon to website! Thank to @Kniksisk (#51)

Minor changes:

• small improves at the asset klonoa-w-sit. Thank to @Kniksisk (#49)