我需要安装一个github包 这是我的代码：
devtools :: install_github ("jgalgarra / kcorebip")
我已经安装了devtool，但是它给我以下错误： 错误：无法从GitHub安装“未知软件包”： 达到超时：10015毫秒后连接超时 这是我在Rprofile.site中配置的：
# Things you might want to change
# options (papersize = "a4")
# options (editor = "notepad")
# options (pager = "internal")
# set the default help type
# options (help_type = "text")
options (help_type = "html")
# set a site library
# .Library.site <- file.path (chartr ("\\", "/", R.home ()), "site-library")
# set a CRAN mirror
# local ({r <- getOption ("repos")
# r ["CRAN"] <- "http: //my.local.cran"
# r ["CRAN"] <- http://cran.us.r-project.org
#options (repos = r)})
local ({r <- getOption ("repos")
r ["Nexus"] <- "http://nexus.uo.edu.cu:8081/repository/R-repository/"
options (repos = r)
})
# Give a fortune cookie, but only to interactive sessions
# (This would need the fortunes package to be installed.)
# if (interactive ())
# fortunes :: fortune ()
我可以修改任何行来安装github还是另一个问题？