Adds custom helpers functions to definitions

Adds custom helpers functions to the (do) definitions
Adds the auto-update config file.
+ picturefill update.json

Important & popular polyfill.  Seems to be on track for a new release every 1-2 months now.

@megawac I assume we don't need an array for `include` if it is only 1 file?
Merge pull request #1646 from anijs/master

Update to the v0.6.0
Merge pull request #1648 from tomByrer/patch-5

+ picturefill update.json