Fall back on require.resolve to find plugins.
Fall back on require.resolve to find plugins.

When loading plugins, this means the local and global node_modules directories
will be searched after the project and plugin/ directories.

This change facilitates the independent distribution of plugins using npm.

ternjs/tern,emallson/tern,ternjs/tern,cloud9ide/tern,cdosborn/tern,eranif/tern,neoclide/tern,ternjs/tern,adrianton3/tern,eranif/tern,MarcelGerber/tern,messfairy/tern,jgiles/tern,talyian/tern,emacsmirror/tern,dorellang/tern,Icenium/tern,angelozerr/tern,anandthakker/tern,emacsmirror/tern,cdosborn/tern,messfairy/tern,emacsmirror/tern,albertinad/tern,Icenium/tern,angelozerr/tern,marijnh/tern,rustemferreira/tern,emallson/tern,mcanthony/tern,fileability/tern,jgiles/tern,dorellang/tern,marijnh/tern,talyian/tern,rustemferreira/tern,fileability/tern,mcanthony/tern,marijnh/tern,MarcelGerber/tern,fileability/tern,talyian/tern,anandthakker/tern,dorellang/tern,messfairy/tern,MarcelGerber/tern,emallson/tern,albertinad/tern,Icenium/tern,neoclide/tern,jgiles/tern,othree/tern,cloud9ide/tern,neoclide/tern,anandthakker/tern,adrianton3/tern,albertinad/tern,eranif/tern,othree/tern,cdosborn/tern,rustemferreira/tern,adrianton3/tern,mcanthony/tern,othree/tern