lots of changes

[Rodrigo Moya <rmoya tsai es>]

Hi all!

I've made lots of source code changes on CVS. First of all, I've moved
all the config stuff (Gda_Server and Gda_Dsn) to the libgda-common
library. This breaks lots of source files, as some of them had #include
<gda-server.h>. So, I've added a gda-client.h file which is the main
header file for the gda-client library, so now, you just include this
file for client applications.

So, there is now a header file for each of the libraries:

gda-common.h
gda-client.h
gda-ui.h

I've also seen that there are many gda-common.h files in the providers,
and that they are useless (they contain the GDA_Connection_QType enum,
which is already defined in gda.h), so please have a look at it, and if
it's not needed, remove it from CVS. If there is something needed, just
move it to another file (gda-*-types.h is a good choice). This is needed
as the servers will make use of the libgda-common library.

Also, I've checked in the gda-srv library which I started time ago. It
does not work right now, but I'll be working on it to provide a default
GDA provider implementation, which will then be used by the providers to
add just the extra functionality. Instead of directly modifying the
current providers to use this library, I've thought of adding a new
provider as a test for the library, and as soon as this provider has all
the functionality, modify the current providers. I'm not starting this
right now, as there are other things I'm working on, so if somebody
wants to try adding a new provider....

Cheers