Stop passing URL and aliasof into lib, revise explanatory comment
Merge branch 'master' into bundle-header
Merge branch 'master' into bundle-header

Conflicts:
	lib/aliases.js
The resolution function must ensure that it returns an array or errors start to occur, if an alias doesn't exist it must return an array passing through the name it was supplied as the only element in the array (indicating that no alias was expanded), this also merges in the changes to the name of the AliasResolver.resolve method correctly
Remove console log
Remove explicit maybe flag ('maybe' inclusion is implicit and the flag is no longer used)
If an alias resolver function can not expand an alias, return undefined. In this case, handle the undefined value and pass the identifier through to the next resolver function.  This also ensures that the rule that included the polyfill is always recorded as an aliasOf and adds some tests specifically for this
Change comment to match code
If a canonical polyfill name is included, don't build an 'alias' including itself.  Only build an alias list if it is resolved by a resolver function.  This commit adds explicit tests for this and expands the logic for cascading this when removing duplicates to use 'if' statements rather than ternary statements (hopefully this is a little clearer)
Merge pull request #53 from Financial-Times/bundle-header

Bundle header