lfs: convert to using exthelper to wrap functions
I'm not 100% sure that upgraderequirements() can be double annotated safely, but
it seems OK based on printing the address of the function being wrapped.
One thing I've noticed is that @eh.reposetup doesn't do the usual check to
ensure that it's a local repo. Should that be baked into @eh.reposetup()
somehow, possibly with a non-default option to skip the check? It seems like a
gaping hole if every function that gets registered needs to add this check.
{
// Enforcing
"eqeqeq" : true, // true: Require triple equals (===) for comparison
"forin" : true, // true: Require filtering for..in loops with obj.hasOwnProperty()
"freeze" : true, // true: prohibits overwriting prototypes of native objects such as Array, Date etc.
"nonbsp" : true, // true: Prohibit "non-breaking whitespace" characters.
"undef" : true, // true: Require all non-global variables to be declared (prevents global leaks)
// Environments
"browser" : true // Web Browser (window, document, etc)
}