Added (libevent,tor) and modified glibc-compat

ports/libevent/build.sh

+# Copyright 2015 The Native Client Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+# following flag are needed only if you want to run samples in devenv
+NACLPORTS_CPPFLAGS+=" -Dmain=nacl_main"
+export LIBS="${NACL_CLI_MAIN_LIB}"
+
+
+ConfigureStep() {
+  if [ "${NACL_LIBC}" = "newlib" ]; then
+    NACLPORTS_CPPFLAGS+=" -I${NACLPORTS_INCLUDE}/glibc-compat"
+    export LIBS+=" -lglibc-compat"
+    # setitimer and getitimer not available in newlib, no plan to implement them
+    #TODO(dt) remove this flag once this issue is sorted.
+    EXTRA_CONFIGURE_ARGS+=" --disable-libevent-regress"
+  fi
+
+  # This flag is not required when NACL_SHARED != 0[default]
+  # however if you come across any problem while static linking,
+  # uncomment following line and try again
+  # EXTRA_CONFIGURE_ARGS+=" --enable-shared=no --enable-static=yes"
+
+  DefaultConfigureStep
+}