Introduce OSCMessageBuilder

[hoijui]

In order to make OSCMessage an immutable object (all fields final), while still having a comfortable way to create messages, we could simply use the builder pattern, like in OSCPortInBuilder.java

This is related to the concurrency issue #4.

[T-Roel]

Good afternoon @hoijui is this issue still necessary to be implemented? I'd like to contribute with the project and I think it will be good to start with it. If you believe it's not necessary, I'd like to know if you recommend another one :) Thanks in advance!

[hannesa2]

If @hoijui is interested on further development, all is fine. Only the merge of existing pull requests is an open task.
I at least made 2 pull requests to see if a further contribution makes sense here.

But if he is no more interested, it would be fair to give an additional maintainer the power to merge, because the community is at least interested.
Let's see, if we get an answer....

[hoijui]

@T-Roel , Sure, please!
Feel free to do so!
Also.. and of the other collaborators, feel free to deal with the resulting PR without my interaction.

[T-Roel]

Thanks to answer back @hoijui I'll take a look at this issue and will apply the resquested changes :)