Add Run/Debug actions line marker in Citrus XML files

[picimako]

Summary

Citrus YAML and Groovy files already have line markers to run/debug corresponding Java test methods. It is time for the XML DSL to have that feature.

Tasks

• Add the run/debug line marker to Citrus XML files.
• Support both regular XML and Spring XML files as well.
• The line marker should be added to:
  • the <test> tag in case of regular XML files. This is a top-level tag, so there will only be one per file.
  • the <testcase> tags in case of Spring XML files. This is not a top-level tag, so there may be more than one of them.
    • can the @CitrusTestSource annotation configuration distinguish between them inside the same XML file?

[picimako]

Both Spring and non-Spring XML file support are completed in v1.0.8.