Added support for the "--repl" argument to LLDB.  

This makes LLDB launch and create a REPL, specifying no target so that the REPL
can create one for itself.  Also added the "--repl-language" option, which
specifies the language to use.  Plumbed the relevant arguments and errors
through the REPL creation mechanism.

llvm-svn: 250773
diff --git a/lldb/scripts/interface/SBDebugger.i b/lldb/scripts/interface/SBDebugger.i
index de58f71..2abffa8 100644
--- a/lldb/scripts/interface/SBDebugger.i
+++ b/lldb/scripts/interface/SBDebugger.i
@@ -377,6 +377,9 @@
                            int  &num_errors,
                            bool &quit_requested,
                            bool &stopped_for_crash);
+    
+    lldb::SBError
+    RunREPL (lldb::LanguageType language, const char *repl_options);
 }; // class SBDebugger
 
 } // namespace lldb