fix(labels): Allow user to label as spam or trash from the dropdown

Also fixes the sort ordering of standard labels in the category picker. Fixes #555

internal_packages/category-picker/lib/category-picker.cjsx

@@ -252,9 +252,12 @@ class CategoryPicker extends React.Component
     @_account = AccountStore.current()
     return unless @_account
 
-    categories = CategoryStore.getStandardCategories()
-      .concat([{divider: true, id: "category-divider"}])
-      .concat(CategoryStore.getUserCategories())
+    if @_account.usesLabels()
+      categories = CategoryStore.getCategories()
+    else
+      categories = CategoryStore.getStandardCategories()
+        .concat([{divider: true, id: "category-divider"}])
+        .concat(CategoryStore.getUserCategories())
 
     usageCount = @_categoryUsageCount(props, categories)
 
@@ -292,9 +295,8 @@ class CategoryPicker extends React.Component
     currentCategoryId = FocusedMailViewStore.mailView()?.categoryId()
 
     if @_account?.usesLabels()
-      hiddenCategories = ["all", "spam", "trash", "drafts", "sent"]
-      if allInInbox
-        hiddenCategories.push("inbox")
+      hiddenCategories = ["all", "drafts", "sent", "archive", "starred", "important"]
+      hiddenCategories.push("inbox") if allInInbox
       return false if category.divider
     else if @_account?.usesFolders()
       hiddenCategories = ["drafts", "sent"]

src/flux/stores/category-store.coffee

@@ -144,13 +144,7 @@ class CategoryStore extends NylasStore
     return unless categoryClass
 
     DatabaseStore.findAll(categoryClass).where(categoryClass.attributes.accountId.equal(account.id)).then (categories=[]) =>
-      @_categoryCache = {}
-      @_categoryCache[category.id] = category for category in categories
-
-      # Compute user categories
-      userCategories = _.reject _.values(@_categoryCache), (cat) =>
-        cat.name in @StandardCategoryNames or cat.name in @HiddenCategoryNames
-      userCategories = userCategories.sort (catA, catB) =>
+      categories = categories.sort (catA, catB) ->
         nameA = catA.displayName
         nameB = catB.displayName
 
@@ -161,10 +155,16 @@ class CategoryStore extends NylasStore
 
         nameA.localeCompare(nameB)
 
-      @_userCategories =  _.compact(userCategories)
+      @_categoryCache = {}
+      for category in categories
+        @_categoryCache[category.id] = category
+
+      # Compute user categories
+      @_userCategories = _.compact _.reject categories, (cat) =>
+        cat.name in @StandardCategoryNames or cat.name in @HiddenCategoryNames
 
       # Compute hidden categories
-      @_hiddenCategories = _.filter _.values(@_categoryCache), (cat) =>
+      @_hiddenCategories = _.filter categories, (cat) =>
         cat.name in @HiddenCategoryNames
 
       # Compute standard categories