Made code block usage consistent across all .md files

README.i18n.md

@@ -15,30 +15,42 @@ You do not need anything from Qt in order to use the final translations.
 
 To update ts files after changing source code:
 
-    ./utils/translations/update-translations.sh
+```bash
+./utils/translations/update-translations.sh
+```
 
 To add a new language, eg Spanish (ISO code es):
 
-    cp translations/monero.ts translations/monero_es.ts
+```bash
+cp translations/monero.ts translations/monero_es.ts
+```
 
 To edit translations for Spanish:
 
-    linguist translations/monero_es.ts
+```bash
+linguist translations/monero_es.ts
+```
 
 To build translations after modifying them:
 
-    ./utils/translations/build-translations.sh
+```bash
+./utils/translations/build-translations.sh
+```
 
 To test a translation:
 
-    LANG=es ./build/release/bin/monero-wallet-cli
+```bash
+LANG=es ./build/release/bin/monero-wallet-cli
+```
 
 To add new translatable strings in the source code:
 
 Use the `tr(string)` function if possible. If the code is in a class, and this class doesn't already have a `tr()` static function, add one, which uses a context named after what `lupdate` uses for the context, usually the fully qualified class name (eg, `cryptonote::simple_wallet`).  If you need to use `tr()` in code that's not in a class, you can use the fully qualified version (eg, `simple_wallet::tr`) of the one matching the context you want. Use `QT_TRANSLATE_NOOP(string)` if you want to specify a context manually.
 
 If you're getting messages of the form:
 
-    Class 'cryptonote::simple_wallet' lacks Q_OBJECT macro
+```
+Class 'cryptonote::simple_wallet' lacks Q_OBJECT macro
+```
 
 all is fine, we don't actually need that here.