[Jslib] xpcom utilities

[pete collins]

I added some xpcom utils functions. There are currently three that are 
not implemented yet.

chrome://jslib/content/utils/xpcom.js

Here is a session:

js> load('/usr/src/jslib/libraries/jslib.js');


*********************
JSLIB DEBUG IS ON
*********************

js> include('chrome://jslib/content/utils/xpcom.js');
js> getClassIDFromProgID('@mozilla.org/file/local;1');
{2e23e220-60be-11d3-8c4a-000064657374}
js> getProgIDFromCID('{2e23e220-60be-11d3-8c4a-000064657374}');
@mozilla.org/file/local;1
js> getInterfaceFromProgID('@mozilla.org/file/local;1');
nsILocalFile,nsIFile
js> getInterfaceFromCID('{2e23e220-60be-11d3-8c4a-000064657374}');
nsILocalFile,nsIFile
js> lookUpError(2147500033);
NS_ERROR_NOT_IMPLEMENTED
js>