Provide directions for cloning repository despite malformed commits #1660

[pdmccormick]

Issue #1660 refers to an issue with commit 942ce6c24c91e6773bfa564bea14f7c769e44f04 that has a malformed date field that causes Git to error out when cloning the repository. While it would be possible to fix this permanently, doing so would involving rewriting all Git history back to 2005, which would be a huge hassle. Instead, why don't we include some helpful directions in the README?