Interact with the user to choose a Bioconductor mirror.
chooseBioCmirror(graphics = getOption("menu.graphics"), ind = NULL,
                 local.only = FALSE)Logical.  If true, use a graphical list: on Windows or
    the macOS GUI use a list box, and on a Unix-alike use a Tk widget if
    package tcltk and an X server are available.  Otherwise use a
    text menu.
Optional numeric value giving which entry to select.
Logical, try to get most recent list from the Bioconductor master or use file on local disk only.
None: this function is invoked for its
  side effect of updating options("BioC_mirror").
This sets the option "BioC_mirror": it is used
  before a call to setRepositories.  The out-of-the-box
  default for that option is NULL, which currently corresponds to
  the mirror https://bioconductor.org.
The ‘Bioconductor (World-wide)’ ‘mirror’ is a network of mirrors providing reliable world-wide access; other mirrors may provide faster access on a geographically local scale.
ind chooses a row in
  R_HOME/doc/BioC_mirrors.csv,
  by number.