Execute the source integrity check.
Execute the source integrity check.

Show a warning if no checksum has been provided by the recipe and show
and error if the provided checksum doesn't match the actual checksum.

ryansch/fpm-cookery,devkid/fpm-cookery,cas-ei/fpm-cookery,kisoku/fpm-cookery,devkid/fpm-cookery,kisoku/fpm-cookery,cas-ei/fpm-cookery,ryansch/fpm-cookery,glensc/fpm-cookery,glensc/fpm-cookery