RFC2, Client for R

Hi, I have changed the code for RbaseXClient.R in such a way that it complies more to the server protocol and to the R-style of coding. - 'execute' has been renamed to 'command' - All the functions in the Command Protocol section return a list with the complete server response. This makes it much easier to handle errors (see lines 8-14 in TestRBaseXClient.R). In the Query Command Protocol section, the functions 'more()' (as being called by results) and 'full()' now return the results, prefixed with a byte that represents the Type ID. Cheers, Ben Engbers