docs/faq/: Some minor FAQ updates that won't change the fact that our FAQ is badly...

docs/faq/: Some minor FAQ updates that won't change the fact that our FAQ is badly structured, full of information ha...

Original commit message from CVS:
* docs/faq/developing.xml:
* docs/faq/faq.xml:
* docs/faq/troubleshooting.xml:
* docs/faq/using.xml:
Some minor FAQ updates that won't change the fact that
our FAQ is badly structured, full of information hardly
anyone new to GStreamer needs to know and lacking lots
of information people constantly ask for.