Changes in version 0.4 (2015-07-09)                   

    o   Use new R 3.2 download methods ("wininet" and "libcurl") when available.

                  Changes in version 0.3 (2013-05-01)                   

    o   `source_url()` function now checks the SHA-1 hash the downloaded file.

    o   Add `sha_url()` function, for finding the SHA-1 hash of a remote file.

                 Changes in version 0.2.2 (2013-02-11)                  

    o   Disable all network tests when running on CRAN, because the connection to the
	remote test website may not be reliable.

                 Changes in version 0.2.1 (2013-02-05)                  

    o   Change https redirection test to not run on CRAN because their Windows build
	 machine has more stringent security settings.

                  Changes in version 0.2 (2013-02-04)                   

    o   Switched to using `Sys.which` to find external programs.

    o   Added tests.

    o   When using curl, follow redirects with http. (It already worked with https.)

    o   Add `source_url` function.