add support for @yields (pangloss#1163)

Author: camflan

extras/jsdoc.vim

@@ -6,7 +6,7 @@ syntax match  jsDocTags         contained "@\(alias\|api\|augments\|borrows\|cla
 " tags containing type and param
 syntax match  jsDocTags         contained "@\(arg\|argument\|cfg\|param\|property\|prop\|typedef\)\>" skipwhite nextgroup=jsDocType
 " tags containing type but no param
-syntax match  jsDocTags         contained "@\(callback\|define\|enum\|external\|implements\|this\|type\|return\|returns\)\>" skipwhite nextgroup=jsDocTypeNoParam
+syntax match  jsDocTags         contained "@\(callback\|define\|enum\|external\|implements\|this\|type\|return\|returns\|yields\)\>" skipwhite nextgroup=jsDocTypeNoParam
 " tags containing references
 syntax match  jsDocTags         contained "@\(lends\|see\|tutorial\)\>" skipwhite nextgroup=jsDocSeeTag
 " other tags (no extra syntax)