this finally kills the dreaded undefined method '+' for nil:NilClass
This eliminates "changed the Gemfile" errors when the Gemfile contains an absolute path, but the lockfile contains a relative path.
Convert LF to CRLF if the existing file has them (Windows /w git config core.autocrlf=true). Addresses issue #810
* vendored_gems should be vendor/bundle * bundle install <path> is deprecated, use bundle install --path <path>
… as well, so the ~= is too strict.