prepare new release to CRAN

[clarkliming]

fix the following notes

• Please always write package names, software names and API (application
  programming interface) names in single quotes in title and description.
  e.g: --> 'SAS'

• Please note that package names are case sensitive.

• Please omit the redundatn "in R" in your title and in the first sentence
  of your description text.

• Please add \value to .Rd files regarding exported methods and explain
  the functions results in the documentation. Please write about the
  structure of the output (class) and also what the output means. (If a
  function does not return a value, please document that too, e.g.
  \value{No return value, called for side effects} or similar)
  Missing Rd-tags:
  get_sas_cfg.Rd: \value
  get_sas_session.Rd: \value
  install_saspy.Rd: \value
  sas_session_ssh.Rd: \value
  sascfg.Rd: \value

• Please do not install packages in your functions, examples or vignette.
  This can make the functions,examples and cran-check very slow.

other examples:
https://github.com/r-spatial/rgee/blob/785034fd0f2bd8a8ef7e7b56570d673014473c11/R/ee_install.R#L4

[clarkliming]

for the issue of "please do not install packages in your functions" I think we could, put these code in text format? or we insist on using that function?