Fix ansible rpm (rebased)

(continuation of #22)

I cleaned dxs.spec from DXS branch:

- include xsce.yml
- substitute DXS for XSCE in paths and texts
- add `Provides: ` directive for xs-config and xs-tools.

To test, 

* build rpm `rpmbuild -bb xsce-server.spec`
* local install in target machine `sudo yum localinstall xsce-server-0.0-1480_gb42a1de.noarch.rpm`
* `sudo runansible`

There is a compiled rpm in https://sugardextrose.org/attachments/download/3281/xsce-server-0.0-1479_geb1f85a.noarch.rpm