[loose parser] Don't tokenize ellipsis when ecmaVersion < 6
[loose parser] Don't tokenize ellipsis when ecmaVersion < 6

Issue marijnh/tern#493

chicoxyzzy/babel,MarcelGerber/acorn,Skillupco/babel,TimothyGu/acorn,babel/babylon,happibum/acorn,mysticatea/acorn,xiemaisi/acorn,claudiopro/babel,MarcelGerber/acorn,cbishopvelti/babylon,ajaxorg/acorn,hulkish/babel,maurobringolf/babel,hzoo/babel,guybedford/babel,ternjs/acorn,PolymerLabs/babel,marijnh/acorn,mathiasbynens/acorn,shuhei/babel,lightscript/babylon-lightscript,PolymerLabs/babel,kaicataldo/babel,babel/babel,MarcelGerber/acorn,gratex/acorn,existentialism/babel,guybedford/babel,guybedford/babel,Rich-Harris/acorn,hulkish/babel,vadzim/babel,happibum/acorn,btmills/acorn,kaicataldo/babel,chicoxyzzy/babel,wcjohnson/babylon-lightscript,ajaxorg/acorn,Rich-Harris/acorn,maurobringolf/babel,btmills/acorn,claudiopro/babel,kellyselden/babel,hzoo/babel,jridgewell/babel,ternjs/acorn,TimothyGu/acorn,vadzim/babel,PolymerLabs/babel,btmills/acorn,kaicataldo/babel,hulkish/babel,jridgewell/babel,shuhei/babel,Rich-Harris/acorn,samwgoldman/babel,marijnh/acorn,recipesjs/ingredients,danez/babylon,gratex/acorn,hzoo/babel,existentialism/babel,samwgoldman/babel,ajaxorg/acorn,marijnh/acorn,jridgewell/babel,mathiasbynens/acorn,babel/babel,happibum/acorn,mathiasbynens/acorn,kellyselden/babel,xiemaisi/acorn,xiemaisi/acorn,maurobringolf/babel,shuhei/babel,mysticatea/acorn,babel/babel,mysticatea/acorn,kellyselden/babel,jridgewell/babel,Skillupco/babel,claudiopro/babel,hulkish/babel,samwgoldman/babel,chicoxyzzy/babel,TimothyGu/acorn,Skillupco/babel,kaicataldo/babel,existentialism/babel,hzoo/babel,chicoxyzzy/babel,babel/babel,gratex/acorn,ternjs/acorn,kellyselden/babel,Skillupco/babel