Rename master to maintainer

app/models/protected_branch.rb

@@ -5,7 +5,7 @@ class ProtectedBranch < ActiveRecord::Base
   protected_ref_access_levels :merge, :push
 
   def self.protected_ref_accessible_to?(ref, user, project:, action:, protected_refs: nil)
-    # Masters, owners and admins are allowed to create the default branch
+    # Maintainers, owners and admins are allowed to create the default branch
     if default_branch_protected? && project.empty_repo?
       return true if user.admin? || project.team.max_member_access(user.id) > Gitlab::Access::DEVELOPER
     end

lib/gitlab/access.rb

@@ -32,7 +32,7 @@ module Gitlab
           "Guest"      => GUEST,
           "Reporter"   => REPORTER,
           "Developer"  => DEVELOPER,
-          "Master"    => MASTER
+          "Maintainer" => MASTER
         }
       end
 
@@ -57,10 +57,10 @@ module Gitlab
 
       def protection_options
         {
-          "Not protected: Both developers and masters can push new commits, force push, or delete the branch." => PROTECTION_NONE,
-          "Protected against pushes: Developers cannot push new commits, but are allowed to accept merge requests to the branch. Masters can push to the branch." => PROTECTION_DEV_CAN_MERGE,
-          "Partially protected: Both developers and masters can push new commits, but cannot force push or delete the branch." => PROTECTION_DEV_CAN_PUSH,
-          "Fully protected: Developers cannot push new commits, but masters can. No-one can force push or delete the branch." => PROTECTION_FULL
+          "Not protected: Both developers and maintainers can push new commits, force push, or delete the branch." => PROTECTION_NONE,
+          "Protected against pushes: Developers cannot push new commits, but are allowed to accept merge requests to the branch. Maintainers can push to the branch." => PROTECTION_DEV_CAN_MERGE,
+          "Partially protected: Both developers and maintainers can push new commits, but cannot force push or delete the branch." => PROTECTION_DEV_CAN_PUSH,
+          "Fully protected: Developers cannot push new commits, but maintainers can. No-one can force push or delete the branch." => PROTECTION_FULL
         }
       end