expanded options for R CMD build and check to work without latex
Merge remote-tracking branch 'parentrepo/master'
treat warnings as errors
add environment option that enables treating warnings as errors, off by default

per Dirk's request
precisely specify log file to check
Merge pull request #71 from krlmlr/69-warnings-are-errors

treat warnings as errors
r-binary-install uses r-install as fallback if not running Linux or FORCE_SOURCE_INSTALL is set
can't use -o when testing with [[
Merge pull request #79 from romainfrancois/master

added dropbox script
Merge pull request #78 from krlmlr/source-install

r-binary-install uses r-install as fallback if not running Linux or FORCE_SOURCE_INSTALL is set
retrying apt-get update with exponentially increasing time intervals until success
maximum time interval between retries is one minute
Retry all apt-get calls, too
Merge pull request #77 from krlmlr/retries

retry fetching files with exponentially increasing timeouts
Tweak ordering. Add a few more useful examples.
Merge pull request #82 from hadley/patch-3

Tweak ordering. Add a few more useful examples.
Merge remote-tracking branch 'parentrepo/master'
create addition 'install_foo' targets for more consistent interface
Merge pull request #1 from eddelbuettel/install_foo

create addition 'install_foo' targets for more consistent interface
more compact case statement