Fix review comments

doc/development/i18n/introduction.md

 # Translate GitLab to your language
-The text in GitLab's user interface is in English by default.
+The text in GitLab's user interface is in American English by default.
 Each string can be translated to other languages.
 As each string is translated, it is added to the languages translation file,
 and will be available in future releases of GitLab.
@@ -17,9 +17,9 @@ Translating strings will help complete and improve each language.
 Before a string can be translated, it must be externalized.
 This is the process where English strings in the GitLab source code are wrapped in a function that
-retrieves the translated string for the users language.
-As new features are added and existing features are updated the surrounding strings are being
+retrieves the translated string for the user's language.
+As new features are added and existing features are updated, the surrounding strings are being
 externalized, however, there are many parts of GitLab that still need more work to externalize all
 strings.
@@ -67,7 +67,7 @@ Requests to become a proof reader will be considered on the merits of previous t
 - Spanish
 - Ukrainian
-If you would like to be added as a proof reader, please [open an issue](https://gitlab.com/gitlab-org/gitlab-ce/issues) and add the `internationalization` label.
+If you would like to be added as a proof reader, please [open an issue](https://gitlab.com/gitlab-org/gitlab-ce/issues).
 ### Release

doc/development/i18n/translation.md

@@ -16,7 +16,7 @@ GitLab is being translated into many languages.
 1. Select the language you would like to contribute translations to by clicking the flag
 1. You will see a list of files and folders.
-  Click `gitlab.pot` top open the translation editor.
+  Click `gitlab.pot` to open the translation editor.
 ### Translation Editor
@@ -31,7 +31,7 @@ The online translation editor is the easiest way to contribute translations.
   If the string to be translated is not clear, you can 'Request Context'
 A glossary of common terms is available in the right panel by clicking Terms.
-Comments can be added to discuss a translation with the community
+Comments can be added to discuss a translation with the community.
 Remember to **Save** each translation.
@@ -58,4 +58,3 @@ suitable level of formality.
 To propose additions to the glossary please
 [open an issue](https://gitlab.com/gitlab-org/gitlab-ce/issues).
-

doc/development/i18n_guide.md

+This document was moved to [development/i18n/externalization.md](i18n/externalization.md).