Knockout:Dealt with implicit any in knockout.d.ts

There are probably still more overloads required for renderTemplate and
renderTemplateForEach as these methods do a lot of different things and
allow many possibilites in terms of types of arguments to be passed.
Knockout: dateItemAlias is optional
Knockout: removed implicit any from knockout.amd.ts
Merge pull request #1236 from johnnyreilly/master

Knockout:Dealt with implicit any in knockout.d.ts and knockout.amd.ts