Berkshelf.lock ignored. Memcached 1.5.0 over 1.4.0 yields chef-client failures.

berks install (and then upload) is ignoring the Berksfile.lock. 4.1.2 is locked to memcached 1.4.0, but 1.5.0 is being downloaded/uploaded. This causes chef-client failures because the 1.5.0 memcached cookbook is in shambles from the memcached-chat/logfilename changes/brokenness.

See: https://github.com/RiotGames/berkshelf/issues/815 and https://github.com/RiotGames/berkshelf/pull/765

This also only seems to be a problem for fresh berks installs. Installs with 1.4.0 already in the berks cache will do the right thing.

The temp fix appears to be specifying 1.4.0 in the Berksfile itself, forcing the version on install over the .lock file. Will fix shortly as soon as I figure out where to put that fix. (master, backport to 4.1-stable?)

@btorch @rpedde-rcbops