Rename all md files to rst

This is plain rename without changing content, to help git track files
history.
Do not touch files that are going to be removed during conversion.

Thanks @parulin for the idea!

developer/debugging/mount-lvm-image.rst

@@ -0,0 +1,54 @@
+---
+lang: en
+layout: doc
+permalink: /doc/mount-lvm-image/
+ref: 46
+title: How to mount LVM images
+---
+
+You want to read your LVM image (e.g., there is a problem where you can't start any VMs except dom0).
+
+1: make the image available for qubesdb.
+From dom0 terminal:
+
+```bash
+# Example: /dev/qubes_dom0/vm-debian-9-tmp-root
+[user@dom0]$ dev=$(basename $(readlink /dev/YOUR_LVM_VG/YOUR_LVM_IMAGE))
+[user@dom0]$ qubesdb-write /qubes-block-devices/$dev/desc "YOUR_LVM_IMAGE"
+```
+
+2: Create a new disposable VM
+
+```bash
+[user@dom0]$ qvm-run -v --dispvm=YOUR_DVM_TEMPLATE --service qubes.StartApp+xterm &
+```
+
+3: Attach the device to your newly created disp VM
+
+From the GUI, or from the command line:
+
+```bash
+[user@dom0]$ qvm-block attach NEWLY_CREATED_DISPVM dom0:$dev
+```
+
+4: Mount the partition you want to, and do what you want with it
+
+```bash
+[user@dispXXXX]$ mount /dev/xvdiX /mnt/
+```
+
+5: Umount and kill the VM
+
+```bash
+[user@dispXXXX]$ umount /mnt/
+```
+
+6: Remove the image from qubesdb
+
+```bash
+[user@dom0]$ qubesdb-rm /qubes-block-devices/$dev/
+```
+
+# References
+
+Please consult this issue's [comment](https://github.com/QubesOS/qubes-issues/issues/4687#issuecomment-451626625).