Failed to load Widgetsets in maven project in eclipse

Failed to load Widgetsets in maven project in eclipse

I have created a vaadin web application using maven in eclipse. In
particular I have used the archetype vaadin-archetype-touchkit as
described in the book of vaadin (20.3.4). Without making any change on the
default generated code I have run it with maven with goals clean package.
Then I compiled the Widgetset. When I try to run it on Tomcat 7, I receive
the strange message from the webpage:
Failed to load the WidgetSet:
<WidgetSet Path>.DefaultWidgetSet.nocache.js
On the console I see also the error messages:
INFO: Requested resource [/VAADIN/themes/reindeer/styles.css] not found
from filesystem or through class loader. Add widgetset and/or theme JAR to
your classpath or add files to WebContent/VAADIN folder.
INFO: Requested resource
[/VAADIN/widgetsets/com.vaadin.DefaultWidgetSet/com.vaadin.DefaultWidgetSet.nocache.js]
not found from filesystem or through class loader. Add widgetset and/or
theme JAR to your classpath or add files to WebContent/VAADIN folder.
INFO: Requested resource [/VAADIN/themes/reindeer/styles.css] not found
from filesystem or through class loader. Add widgetset and/or theme JAR to
your classpath or add files to WebContent/VAADIN folder.
It has struck me maven has not created a web.xml file, although I have
read in the tutorial that it is no more necessary in vaadin 7. I have read
the similar question where it is proposed that an adjustment in web.xml
file should be done. Should I infer that I have also to create a web.xml
file manually?
I find strange as well, that when I tried the same procedure with the
archetype for a typical vaadin 7 application, it runs properly. Since I
have to develop a touchkit-application I would appreciate any
suggestion-idea abut what could be missing on my original attempt.