Bumped OpenFST implementation to openfst-1.3.3-CL41851770.

Updated OpenFST implementation to the most recent version
used by Greco3 (corresponds to nlp::fst exported at Perforce
CL 41851770).

In particular this version has an improved PDT support.

Change-Id: I5aadfc962297eef73922c67e7d57866f11ee7d81
diff --git a/configure.ac b/configure.ac
index 908a6d5..df9ba18 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1,4 +1,4 @@
-AC_INIT([OpenFst], [1.3.2], [help@www.openfst.org])
+AC_INIT([OpenFst], [1.3.3], [help@www.openfst.org])
 AM_INIT_AUTOMAKE([foreign nostdinc -Wall -Werror])
 
 AC_PROG_CXX
@@ -85,20 +85,6 @@
               [], [enable_pdt=no])
 AM_CONDITIONAL([HAVE_PDT], [test "x$enable_pdt" != xno])
 
-AC_ARG_WITH([icu],
-  [AS_HELP_STRING([--with-icu],
-    [enable UTF8 support using the ICU Library])],
-  [],
-  [with_icu=no])
-AS_IF([test "x$with_icu" != xno],
-  [AC_CHECK_ICU(
-    [4.2],
-    [AC_DEFINE([HAVE_ICU],
-      [1],
-      [Define to 1 if you have the ICU library.])],
-    [AC_MSG_FAILURE(
-      [--with-icu was given, but ICU Library v. 4.2 or newer not found])])])
-
 AC_SUBST([libfstdir], [${libdir}/fst])
 
 AC_OUTPUT