Doxygen: rename all .dox files to end with .md

Using a standard ending here will let other tools that expect
markdown understand our output here.

This commit was automatically generated with:

   for fn in $(find src -name '*.dox'); do \
      git mv "$fn" "${fn%.dox}.md"; \
   done

1 files changed, 14 insertions, 0 deletions

diff --git a/src/lib/dispatch/lib_dispatch.md b/src/lib/dispatch/lib_dispatch.md
new file mode 100644
index 0000000000..153ca50080
--- /dev/null
+++ b/src/lib/dispatch/lib_dispatch.md
@@ -0,0 +1,14 @@
+@dir /lib/dispatch
+@brief lib/dispatch: In-process message delivery.
+
+This module provides a general in-process "message dispatch" system in which
+typed messages are sent on channels. The dispatch.h header has far more
+information.
+
+It is used by by \refdir{lib/pubsub} to implement our general
+inter-module publish/subscribe system.
+
+This is not a fancy multi-threaded many-to-many dispatcher as you may be used
+to from more sophisticated architectures: this dispatcher is intended only
+for use in improving Tor's architecture.
+