[Rd] a couple of small problems with current R devel branch

[Hin-Tak Leung]

These are small enough problems with R devel branch yesterday I thought I'll just post here and hope somebody will fix them soon (or may have already been fixed today), rather than filing at the bugzilla.

- "R CMD check --use-valgrind --use-gct <mypackage>" gives:

------------------------------
Error in gzfile(file, "rb") : 
  can only weakly reference/finalize reference objects
Calls: library -> find.package -> lapply -> FUN -> readRDS -> gzfile
Execution halted
------------------------------

That doesn't comes from my code - it appears that the "--use-valgrind --use-gct " options does not like readRDS(), which is in the base package.

- a small typo in "R/src/library/base/man/readRDS.Rd" while I looked at the error above - note the repeated "support for":

--------------------
  interface has been stable since \R 1.7.0, except that support for
  support for types of compression was added in \R 2.10.0 (previously
--------------------

TIA.