update holder.js to v2.3; refs 12196

BS3 commits: 77ff3871fdb008198497a4d2767062a3137d11f8
update less.js to v1.6.1 & use accurate filename; refs 12196

BS3 commits: ef22ab5aedb10e334eb4177922e26936ca11fa54
update to FileSaver.js version 2013-12-27 / 0055d054ac

BS3 commits: f972331a10a7cfab6a2f07f48945e67f11499f6c
add Blob.js separate from filesaver.js

BS3 commits: 4b5e73b842104cb2cc93fe46224b8d50587b296e
grunt dist build-customizer

BS3 commits: 80bed836e0a699d43c483e9957d153edff1ce3d1