Update tinygettext. Fixes #2522.

Updates to upstream changeset f71a8e5e84bffadd61ac93768b332262989844fd,
with some additions
that will be submitted upstream (without the addition of precompiled.h
and win32 dirent).

This was SVN commit r16462.

source/third_party/tinygettext/src/unix_file_system.cpp

@@ -59,7 +59,7 @@ UnixFileSystem::open_directory(const std::string& pathname)
     return files;
   }
 }
-  
+
 std::unique_ptr<std::istream>
 UnixFileSystem::open_file(const std::string& filename)
 {