Migration to Maven

Hello,

I would like to ask migration about build system from ant to maven.

According to github (https://github.com/pgjdbc/pgjdbc/pull/322) there is some work behind it.

Anyway what do you think about creating profiles in ant/maven?

For example profile where sspi and osgi would be optional.

+ Would you accept patch implementing class which would just has methods from SSPIClient.java and throws unsupported
exception(Real implementation would be in class which inherit from this simple class). 

After proposed changes GNU/Linux distributions (namely fedora) should stick close to upstream without any bigger
patchesor hacks. 

Let me know.

Pavel Kajaba