add pre fetching of need docker images
add pre fetching of need docker images

zutherb/AppStash,vivekjuneja/AppStash,vivekjuneja/AppStash,vivekjuneja/AppStash,zutherb/AppStash,zutherb/AppStash,vivekjuneja/AppStash,zutherb/AppStash,zutherb/AppStash,vivekjuneja/AppStash,vivekjuneja/AppStash,zutherb/AppStash,vivekjuneja/AppStash,vivekjuneja/AppStash,zutherb/AppStash,zutherb/AppStash