Fixes for the Intel compiler version 16 and 17 (#223)

Proposed patch to master branch:
* Qualify template in `indirect_view` to accommodate incorrect function template specialization determination (icpc ignores §14.8.2.4/9 rule on lvalue versus rvalue template arguments).
* Use parenthesis constructors for type parameter in `pointer_proxy`, as icpc has not adopted the corrected behaviour for DR#1467 [http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_defects.html#1467].

src/util/indirect.hpp

@@ -38,7 +38,9 @@ template <typename RASeq, typename Seq>
 auto indirect_view(RASeq& data, const Seq& index_map)
 DEDUCED_RETURN_TYPE(transform_view(index_map, impl::indirect_accessor<RASeq&>(data)));
 
-template <typename RASeq, typename Seq>
+// icpc 17 fails to disambiguate without further qualification, so
+// we replace `template <typename RASeq, typename Seq>` with the following:
+template <typename RASeq, typename Seq, typename = util::enable_if_t<!std::is_reference<RASeq>::value>>
 auto indirect_view(RASeq&& data, const Seq& index_map)
 DEDUCED_RETURN_TYPE(transform_view(index_map, impl::indirect_accessor<RASeq>(std::move(data))));
 

src/util/iterutil.hpp

@@ -89,8 +89,8 @@ auto back(Seq& seq) -> decltype(*std::begin(seq)) {
  */
 template <typename V>
 struct pointer_proxy: public V {
-    pointer_proxy(const V& v): V{v} {}
-    pointer_proxy(V&& v): V{std::move(v)} {}
+    pointer_proxy(const V& v): V(v) {}
+    pointer_proxy(V&& v): V(std::move(v)) {}
     const V* operator->() const { return this; }
 };