XAR plugin does not properly escape document names containing a dot in package.xml

The issues is that after running mvn xar:package or mvn clean install in a Maven module you are unable to import the pages having a dot in their name.

Steps to reproduce:

• create a page in Main space, called "XWiki 5.0.2"
• Export this page
• Open the XAR archive, and extract the XWiki 5.0.2.xml into a Maven module which has a pom.xml configured to support the xar plugin
• run mxn:xar format and then mvn clean install
• re-import the package in the wiki after you deleted the previously created page. You will see that from the import page, XWiki will see no document inside your XAR. It's like you have an empty XAR you'd want to import

The problem seems to be package.xml which is generated by the xar plugin. It does not escape properly the page name.

The exported page from the wiki has in package.xml

<file defaultAction="0" language="">Main.XWiki 5\.0\.2</file>

and the one generated by XAR plugin is

<file language="" defaultAction="0">Main.XWiki 5.0.2</file>