Conflicts between syntax.std.tuple and syntax.std.product

[alexarchambault]

Already briefly discussed here #296, but still applies:

scala> import syntax.std.tuple._, syntax.std.product._
import syntax.std.tuple._
import syntax.std.product._

scala> case class Foo(i: Int, s: String)
defined class Foo

scala> Foo(2, "a").to[List]
<console>:19: error: type mismatch;
 found   : Foo
 required: ?{def to: ?}
Note that implicit conversions are not applicable because they are ambiguous:
 both method productTupleOps in trait LowPriorityTuple of type [P <: Product](p: P)shapeless.syntax.std.TupleOps[P]
 and method productOps in object product of type [P <: Product](p: P)shapeless.syntax.std.ProductOps[P]
 are possible conversion functions from Foo to ?{def to: ?}
              Foo(2, "a").to[List]
                 ^
<console>:19: error: value to is not a member of Foo
              Foo(2, "a").to[List]
                          ^