Add zlib module:

The zlib module is a port of ZLib's raw deflate
algorithm to header-only C++11.

scripts/build-and-test.sh

@@ -70,7 +70,7 @@ function run_tests_with_valgrind {
     else
       # TODO --max-stackframe=8388608
       # see: https://travis-ci.org/vinniefalco/Beast/jobs/132486245
-      valgrind --error-exitcode=1 "$x"
+      valgrind --suppressions=./scripts/valgrind.supp --error-exitcode=1 "$x"
     fi
   done
 }

scripts/valgrind.supp

@@ -0,0 +1,10 @@
+{
+   zlib_fill_window_no_init
+   Memcheck:Cond
+   fun:fill_window
+}
+{
+   beast_fill_window_no_init
+   Memcheck:Cond
+   fun:_ZN5beast4zlib6detail14deflate_stream11fill_windowIvEEvRNS0_8z_paramsE
+}