Retry doesn't blow away the build dir, should it ?

[davidx]

When calling 'thumbot retry' it operates on the same build dir.
Some builds don't clean up to a pristine state before each build and thus a case could be made for blowing away the build dir entirely for it to be fresh.

This build: basho/riak_repl#764 (comment) had to be manually cleaned up for retry.

Should we blow away the build dir during retries ?

[JeetKunDoug]

I would say "yes" - the most typical case that I've run across is when Github fails to let you clone some repository, but git creates the directory - get-deps or some other step in the build process will then continue to fail until you delete at least that directory and do get-deps again.

[davidx]

Merged and deployed: #61