Fix formatting of command lines in Docker.md

These were using "inline code" syntax rather than code block. Code
blocks look better and make the lines easier to cut and paste when
editing the file.

Author: nud

Docker.md

@@ -22,9 +22,12 @@ docker-compose run linuxfr.org bin/rails db:setup
 Finally, the environment is ready and you can open [http://dlfp.lo](http://dlfp.lo)
 in your favorite browser.
 
-Note: to be able to access this URL, you'll need to add the line
-`127.0.0.1 dlfp.lo image.dlfp.lo` to the `/etc/hosts` file of your
-machine.
+Note: to be able to access this URL, you'll need to add the following line
+into the `/etc/hosts` file of your machine:
+
+```
+127.0.0.1 dlfp.lo image.dlfp.lo
+```
 
 Personalize configuration
 =========================
@@ -58,7 +61,9 @@ will directly detect changes and apply them on next page reload.
 Furthermore, if you need to access the Rails console, you need a second
 terminal and run:
 
-`docker-compose run linuxfr.org bin/rails console`
+```
+docker-compose run linuxfr.org bin/rails console
+```
 
 Note: currently, we didn't configure rails to show directly the
 `webconsole` in your browser. That's just because of time needed to
@@ -76,15 +81,19 @@ To get help about writing tests, see the
 
 To run tests with Docker environment, you need to use this command:
 
-`docker-compose run linuxfr.org bin/rails test -v`
+```
+docker-compose run linuxfr.org bin/rails test -v
+```
 
 Inspect database schema
 =======================
 
 In case you need to inspect the database, you need a second terminal
 and run:
 
-`docker-compose run database mysql -hdatabase -ulinuxfr_rails -p linuxfr_rails`
+```
+docker-compose run database mysql -hdatabase -ulinuxfr_rails -p linuxfr_rails
+```
 
 By default, the requested password is the same as the username.
 
@@ -94,12 +103,16 @@ Apply database migrations
 In case you need to apply new database migrations, you need a second
 terminal and run:
 
-`docker-compose run linuxfr.org bin/rails db:migrate`
+```
+docker-compose run linuxfr.org bin/rails db:migrate
+```
 
 If you had issue and want to reset all data in your database system,
 use:
 
-`docker-compose run linuxfr.org bin/rails db:reset`
+```
+docker-compose run linuxfr.org bin/rails db:reset
+```
 
 Services provided by the docker-compose
 =======================================