Add lang + ref tags to frontmatter

Those are fields used by the language switcher to correlate pages across
different languages, even if they have different names/paths/titles.
They are generated with the prepare_for_translation.py script.

developer/services/admin-api.md

@@ -1,4 +1,5 @@
 ---
+lang: en
 layout: doc-full
 permalink: /doc/admin-api/
 redirect_from:
@@ -6,6 +7,7 @@ redirect_from:
 - /doc/mgmt1/
 - /doc/mgmt-architecture/
 - /doc/admin-api-architecture/
+ref: 36
 title: Admin API
 ---
 

developer/services/dom0-secure-updates.md

@@ -1,10 +1,12 @@
 ---
+lang: en
 layout: doc
 permalink: /doc/dom0-secure-updates/
 redirect_from:
 - /en/doc/dom0-secure-updates/
 - /doc/Dom0SecureUpdates/
 - /wiki/Dom0SecureUpdates/
+ref: 43
 title: Dom0 Secure Updates
 ---
 

developer/services/dvm-impl.md

@@ -1,10 +1,12 @@
 ---
+lang: en
 layout: doc
 permalink: /doc/dvm-impl/
 redirect_from:
 - /en/doc/dvm-impl/
 - /doc/DVMimpl/
 - /wiki/DVMimpl/
+ref: 34
 title: DVMimpl
 ---
 

developer/services/qfilecopy.md

@@ -1,10 +1,12 @@
 ---
+lang: en
 layout: doc
 permalink: /doc/qfilecopy/
 redirect_from:
 - /en/doc/qfilecopy/
 - /doc/Qfilecopy/
 - /wiki/Qfilecopy/
+ref: 35
 title: Qfilecopy
 ---
 

developer/services/qfileexchgd.md

@@ -1,10 +1,12 @@
 ---
+lang: en
 layout: doc
 permalink: /doc/qfileexchgd/
 redirect_from:
 - /en/doc/qfileexchgd/
 - /doc/Qfileexchgd/
 - /wiki/Qfileexchgd/
+ref: 40
 title: Qfileexchgd
 ---
 

developer/services/qmemman.md

@@ -1,10 +1,12 @@
 ---
+lang: en
 layout: doc
 permalink: /doc/qmemman/
 redirect_from:
 - /en/doc/qmemman/
 - /doc/Qmemman/
 - /wiki/Qmemman/
+ref: 41
 title: Qmemman
 ---
 

developer/services/qrexec-internals.md

@@ -1,4 +1,5 @@
 ---
+lang: en
 layout: doc
 permalink: /doc/qrexec-internals/
 redirect_from:
@@ -6,6 +7,7 @@ redirect_from:
 - /en/doc/qrexec3-implementation/
 - /doc/Qrexec3Implementation/
 - /wiki/Qrexec3Implementation/
+ref: 39
 title: 'Qrexec: Qubes RPC internals'
 ---
 

developer/services/qrexec-socket-services.md

@@ -1,6 +1,8 @@
 ---
+lang: en
 layout: doc
 permalink: /doc/qrexec-socket-services/
+ref: 42
 title: 'Qrexec: Socket-based services'
 ---
 

developer/services/qrexec.md

@@ -1,4 +1,5 @@
 ---
+lang: en
 layout: doc
 permalink: /doc/qrexec/
 redirect_from:
@@ -9,6 +10,7 @@ redirect_from:
 - /en/doc/qrexec/
 - /doc/Qrexec/
 - /wiki/Qrexec/
+ref: 37
 title: 'Qrexec: secure communication across domains'
 ---
 

developer/services/qrexec2.md

@@ -1,4 +1,5 @@
 ---
+lang: en
 layout: doc
 permalink: /doc/qrexec2/
 redirect_from:
@@ -6,6 +7,7 @@ redirect_from:
 - /en/doc/qrexec2-implementation/
 - /doc/Qrexec2Implementation/
 - /wiki/Qrexec2Implementation/
+ref: 38
 title: Qrexec2
 ---