functions to read decoy accessions from fasta file

src/resources/catalog_label.xml

 <catalog>
     <isotope_label_list id="dimethyl">
-<isotope_label id="light">
+        <isotope_label id="light">
     		<mod at="Nter" value="28.0" acc="MOD:00429"/>
     		<mod at="K" value="28.0" acc="MOD:00429"/>
     	</isotope_label>
@@ -12,5 +12,5 @@
     		<mod at="Nter" value="36.0" />
     		<mod at="K" value="36.0" />
     	</isotope_label>
-        </isotope_label_list>
-    </catalog>
+    </isotope_label_list>
+</catalog>