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

6 files changed, 0 insertions, 0 deletions

diff --git a/src/core/core.dox b/src/core/core.md
index 8ecc43eaae..8ecc43eaae 100644
--- a/src/core/core.dox
+++ b/src/core/core.md
diff --git a/src/core/crypto/core_crypto.dox b/src/core/crypto/core_crypto.md
index 26ade1f8f8..26ade1f8f8 100644
--- a/src/core/crypto/core_crypto.dox
+++ b/src/core/crypto/core_crypto.md
diff --git a/src/core/mainloop/core_mainloop.dox b/src/core/mainloop/core_mainloop.md
index fee8a8179c..fee8a8179c 100644
--- a/src/core/mainloop/core_mainloop.dox
+++ b/src/core/mainloop/core_mainloop.md
diff --git a/src/core/or/core_or.dox b/src/core/or/core_or.md
index 0b4d430a00..0b4d430a00 100644
--- a/src/core/or/core_or.dox
+++ b/src/core/or/core_or.md
diff --git a/src/core/or/dataflow.dox b/src/core/or/dataflow.md
index 1098701780..1098701780 100644
--- a/src/core/or/dataflow.dox
+++ b/src/core/or/dataflow.md
diff --git a/src/core/proto/core_proto.dox b/src/core/proto/core_proto.md
index ad43bc5846..ad43bc5846 100644
--- a/src/core/proto/core_proto.dox
+++ b/src/core/proto/core_proto.md