Project-Structure.md

@@ -6,8 +6,10 @@
 
 ### my/eXist/extensions/module/src<br/>my/eXist/src<br/>my/eXist/webapp
 
-MOM-CA uses the [eXist Native XML database](http://exist-db.org/) as its XRX application server. The source code extending or patching the eXist application server is located under [my/eXist](../tree/master/my/eXist).
+MOM-CA uses and in some parts extends the [eXist application server](http://exist-db.org/). The source code extending or patching eXist is located under [my/eXist](../tree/master/my/eXist). eXist provides an interface to write custom XQuery modules extending the function library. Following this , MOM-CA implements a custom XQuery modules:
 
+* an Excel module for the conversion of Excel sheets into XML
+* a text difference module
 
 ### my/XRX/src/core<br/>my/XRX/src/mom