Bump mod version

gradle.properties

@@ -2,6 +2,6 @@ minecraft_version=1.15
 yarn_version=1.15+build.1
 fabric_loader_version=0.7.2+build.174
 fabric_version=0.4.20+build.273-1.15
-mod_version=2.7.1
+mod_version=2.8.0
 modmenu_version=1.7.14-unstable.19w42a+build.10
 nec_version=1.1.5+1.15.1