[Rd] Suppress LaTeX log during R CMD build

[Yihui Xie]

Hi,

When a package's documentation contains \Sexpr{}, R CMD build will
build the manual to PDF. I wonder if the full LaTeX log could be
suppressed in this case. Currently it looks like this:

$ R CMD build foo

* checking for file ‘foo/DESCRIPTION’ ... OK
* preparing ‘foo’:
* checking DESCRIPTION meta-information ... OK
* installing the package to process help pages
* building the PDF package manual
Hmm ... looks like a package
Converting Rd files to LaTeX ......
Creating pdf output from LaTeX ...

This is pdfTeX, Version 3.14159265-2.6-1.40.17 (TeX Live 2016)
(preloaded format=pdflatex)
 restricted \write18 enabled.
entering extended mode

(/private/var/folders/8r/zh8x49md6vsgskh23jrmy7p80000gn/T/RtmpWxPLW3/Rbuild52f3
1a8c19c2/foo/.Rd2pdf21235/Rd2.tex
LaTeX2e <2016/03/31>
Babel <3.9r> and hyphenation patterns for 22 language(s) loaded.
(/usr/local/texlive/2016basic/texmf-dist/tex/latex/base/book.cls
Document Class: book 2014/09/29 v1.4h Standard LaTeX document class
(/usr/local/texlive/2016basic/texmf-dist/tex/latex/base/bk10.clo))
(/Library/Frameworks/R.framework/Resources/share/texmf/tex/latex/Rd.sty
....

Regards,
Yihui
--
Yihui Xie <xieyihui at gmail.com>
Web: http://yihui.name