Add heapqueue module to doc index (#6655)

Add copyright header to heapqueue modlue

lib/pure/collections/heapqueue.nim

@@ -1,3 +1,12 @@
+
+#
+#
+#            Nim's Runtime Library
+#        (c) Copyright 2016 Yuriy Glukhov
+#
+#    See the file "copying.txt", included in this
+#    distribution, for details about the copyright.
+
 ##[ Heap queue algorithm (a.k.a. priority queue). Ported from Python heapq.
 
 Heaps are arrays for which a[k] <= a[2*k+1] and a[k] <= a[2*k+2] for

web/website.ini

@@ -63,6 +63,7 @@ srcdoc2: "deprecated/pure/ftpclient;pure/collections/chains"
 srcdoc2: "pure/asyncfile;pure/asyncftpclient"
 srcdoc2: "pure/md5;pure/rationals"
 srcdoc2: "posix/posix;pure/distros;pure/oswalkdir"
+srcdoc2: "pure/collections/heapqueue"
 srcdoc2: "pure/fenv;pure/securehash;impure/rdstdin"
 srcdoc2: "pure/basic2d;pure/basic3d;pure/mersenne;pure/coro;pure/httpcore"
 srcdoc2: "pure/bitops;pure/nimtracker;pure/punycode;pure/volatile"