Clean up language for building multiplatform projects (#1245)
Clean up language for building multiplatform projects (#1245)

Unify the language explaining the same thing when describing what host OS-es are supported. 
It's "drier" but may help non-native English speakers as it reduces complexity.
hltj/kotlin-web-site-cn,hltj/kotlin-web-site-cn,hltj/kotlin-web-site-cn,JetBrains/kotlin-web-site,hltj/kotlin-web-site-cn,JetBrains/kotlin-web-site,JetBrains/kotlin-web-site,JetBrains/kotlin-web-site,hltj/kotlin-web-site-cn,JetBrains/kotlin-web-site,hltj/kotlin-web-site-cn,JetBrains/kotlin-web-site