添加了 Clojure、R 的官方镜像源

Author: HeZongLun

src/recipe/lang/Clojure.c

@@ -24,7 +24,7 @@ pl_clojure_prelude ()
   chef_allow_user_define(this);
 
   def_sources_begin()
-  {&UpstreamProvider, NULL, DelegateToUpstream},
+  {&UpstreamProvider,"https://repo.clojars.org/", DelegateToUpstream},
   {&MirrorZ,         "https://mirrors.cernet.edu.cn/clojars/",        DelegateToMirror},
   {&Tuna,            "https://mirrors.tuna.tsinghua.edu.cn/clojars/", DelegateToMirror},
   {&Nju,             "https://mirror.nju.edu.cn/clojars/",             DelegateToMirror},

src/recipe/lang/R.c

@@ -25,7 +25,7 @@ pl_r_prelude ()
 
   // 以下注释的，是不含有bioconductor的镜像站，我们在换cran的同时，也直接帮助用户换bioconductor
   def_sources_begin()
-  {&UpstreamProvider, NULL, DelegateToUpstream},
+  {&UpstreamProvider, "https://cran.r-project.org/", DelegateToUpstream},
   {&Sjtug_Zhiyuan,    "https://mirrors.sjtug.sjtu.edu.cn/cran/",    DelegateToMirror},
   // {&Ali,           "https://mirrors.aliyun.com/CRAN/",           DelegateToMirror},
   {&Tuna,             "https://mirrors.tuna.tsinghua.edu.cn/CRAN/", DelegateToMirror},