Add abstract, final, and override to rust.vim keyword list

Author: hydhknn

src/etc/vim/syntax/rust.vim

@@ -54,7 +54,7 @@ syn match rustMacroRepeatCount ".\?[*+]" contained
 syn match rustMacroVariable "$\w\+"
 
 " Reserved (but not yet used) keywords {{{2
-syn keyword   rustReservedKeyword alignof be do offsetof priv pure sizeof typeof unsized yield
+syn keyword   rustReservedKeyword alignof be do offsetof priv pure sizeof typeof unsized yield abstract final override
 
 " Built-in types {{{2
 syn keyword   rustType        int uint float char bool u8 u16 u32 u64 f32