Added bastion and (dummy) rexec docs
diff --git a/Doc/lib/librexec.tex b/Doc/lib/librexec.tex
new file mode 100644
index 0000000..76e63fc
--- /dev/null
+++ b/Doc/lib/librexec.tex
@@ -0,0 +1,5 @@
+\section{Standard Module \sectcode{rexec}}
+\stmodindex{rexec}
+\renewcommand{\indexsubitem}{(in module rexec)}
+
+XXX To be provided.