Packrat 0.4.2

Packrat 0.4.2

• Packrat properly infers whether a project is an R package. A project
  with a DESCRIPTION file that has no Type: field, or has the
  Type: Package field, will be considered as an R package.
• Custom library paths can be set through the R_PACKRAT_LIB_DIR environment
  variable, which can be useful when using Packrat for non-local dependency
  management or deployment.
• A bug in the propagation of BioC repositories was fixed.
• Symlinks to R packages are created and destroyed more conservatively; this
  should help prevent problems where multiple R processes are acting within
  a single Packrat project.
• The autoloader was not properly created in rare cases (thanks, @krlmlr!)
• install_local now forces lib and repos to be passed as named arguments,
  to avoid insidious errors. (#162)
• Packrat no longer removes the lockfile on disable; rather, it simply removes
  the autoloader. (#161)
• Packrat projects can now be non-interactively bootstrapped using the command:
  R --vanilla -f packrat/init.R --args --bootstrap-packrat. (#158)
• packrat::bundle() gains an 'omit.cran.src' argument, for ignoring package
  sources that are retrievable from CRAN. (#156)
• Packrat now understands how to install packages from custom CRAN-like
  repositories. (#153)
• Packrat now infers itself to be a git-managed project if any of its parent
  directories contains a .git folder. This ensures packrat projects included
  as sub-directories of a git-managed folder are properly understood as git-managed
  projects.
• packrat::bundle() gains an 'include.vcs.history' argument, for
  specifying whether VCS history folders (e.g. .git/, .svn/) should
  be packaged as part of the bundle. (#159)
• packrat::bundle() gains an 'include.bundles' argument, for specifying
  whether previously generated bundles are included as part of new bundles.
• Packrat now properly bundles projects on Windows (files in the packrat
  folder were not properly bundled when using the internal version of R's tar)
  (#152)
• Packrat gains the 'load.external.packages.on.startup' option, to control
  whether external packages are loaded on startup.
• Allow users to specify packrat itself as an external package (experimental, #147)
• The automatic snapshot mechanism now re-uses the available.packages()
  cache, to avoid unnecessary internet requests to CRAN.
• packrat::status() no longer asks you to uninstall packages that are
  found within the Suggests: field of the project's R package dependency
  chain, but does not require you to track these packages in the lockfile
  either. (#109)
• Downloads are now retried (up to a default of 5 times) on failure -- this
  should help with intermittent timeouts when e.g. downloading archives from
  GitHub. (#134)
• Packrat now adds .Rprofile to the .Rbuildignore file used for package
  development. (#138)