RExecServer available as a git repository

The RExecServer source is now available as a git repository. Once I figure out what exactly they mean I will be "mobbing" it to allow for patch submission. The binary hasn't been updated, but the source fixes a few reported problems with the pager() and some graphics issues (clipping mostly). It also adds the ability to specify the usual command-line options except for the gui related ones (for obvious reasons).