do not throw by pointer in xcesreader

libcorpus2/io/xcesreader.cpp

@@ -82,7 +82,7 @@ XcesReader::XcesReader(const Tagset& tagset, const std::string& filename, bool d
 	this->is_owned_.reset(new std::ifstream(filename.c_str(), std::ifstream::in));
 
 	if (this->is_owned_->bad()) {
-		throw new Corpus2Error("File not found!");
+		throw Corpus2Error("File not found!");
 	}
 	else {
 		this->is_ = is_owned_.get();