Add GUID support to more filters including XML

[Former user]

Original [issue 91](https://code.google.com/p/okapi/issues/detail?id=91) created by @ysavourel on 2009-07-16T22:23:42.000Z:

Many formats could make use of GUID's such as those found in Java Property files. Most filters don't have an option to find these unique ids and attach them to the TextUnit.

XML-based Java Property is one format where this will become very important for alignment and TM.

HTML and XML formats in general may provide specific ID's as attributes that can be detected by the filter using regex or other rules.

[Former user]

Comment [1.](https://code.google.com/p/okapi/issues/detail?id=91#c1) originally posted by @ysavourel on 2009-07-16T22:38:29.000Z:

+1. I've started to implement that, but that's not done yet. Many formats can take advantage of this.

[Former user]

Comment [2.](https://code.google.com/p/okapi/issues/detail?id=91#c2) originally posted by @ysavourel on 2009-07-17T16:53:33.000Z:

I've added support for defining an idPointer in the XML filter parameters rules and to support xml:id as well. The JavaProperties configuration now recognizes the 'key' attribute as the resname of the extracted text unit.

[Former user]

Comment [3.](https://code.google.com/p/okapi/issues/detail?id=91#c3) originally posted by @ysavourel on 2009-07-20T12:01:13.000Z:

The feature has been added and tested.