update AndroidManifest.xml and properties.xml files to handle XML response format.

Authentic job API's JSON response header has text/plain as content-type
instead of application/json, hence robospice JSON converter
MappingJacksonHttpMessageConverter is unable to parse and deserialize
JSON object to data model. Modification is made to return API response
in XML format.
add simple-xml jar file to the library folder for handling XML format API response.
update data controller class to instantiate XmlSpringAndroidSpiceService spice manager object.
add job_listing xml file for job listing user interface.
modify data model structure and request objects to accommodate response data type change from JSON to XML.