Clean up and streamline config files to use with multiple suits, shoes, insoles

[yeshasvitirupachuri]

Currently, the two configuration files needed to run two xsens suits at the same time are available in DEMO-laptop branch of the upstream. The files are:

• https://github.com/robotology/wearables/blob/DEMO-laptop/app/xml/XsensSuitWearableDevice.xml
• https://github.com/robotology/wearables/blob/DEMO-laptop/app/xml/XsensSuitWearableDevice_second.xml

This is not a clean solution as we have to maintain these two files and update them separately in case of new parameters with future updates. Ideally, it is better to have a single xml configuration file, that takes a prefix parameter as input and launch the wearable device ports with that prefix. @traversaro is there anyway to pass a argument while launching yarprobotinterface with an xml configuration file.

CC @lrapetti @fjandrad @claudia-lat @diegoferigo @DanielePucci