Second pass on fixing up documentation. Still some links not fixed.

src/io/history.h

@@ -0,0 +1,14 @@
+/*
+ * history.h
+ * 
+ * Maintain, and recall, a history of things which have been read from standard
+ * input. Necessarily the history must be stored on the user session, and not be
+ * global.
+ *
+ * I *think* history will be maintained as a list of forms, not of strings, so
+ * only forms which have successfully been read can be recalled, and forms which
+ * have not been completed when the history function is invoked will be lost. 
+ *
+ * (c) 2025 Simon Brooke <simon@journeyman.cc>
+ * Licensed under GPL version 2.0, or, at your option, any later version.
+ */