Add documentation link

Flow.Launcher.Infrastructure/Constant.cs

@@ -21,6 +21,7 @@ public static class Constant
         public static readonly string PreinstalledDirectory = Path.Combine(ProgramDirectory, Plugins);
         public const string Issue = "https://github.com/Flow-Launcher/Flow.Launcher/issues/new";
         public static readonly string Version = FileVersionInfo.GetVersionInfo(Assembly.Location.NonNull()).ProductVersion;
+        public const string Documentation = "https://flow-launcher.github.io/docs/#/usage-tips";
 
         public static readonly int ThumbnailSize = 64;
         private static readonly string ImagesDirectory = Path.Combine(ProgramDirectory, "Images");

Flow.Launcher/Languages/en.xaml

@@ -107,6 +107,7 @@
         or go to https://github.com/Flow-Launcher/Flow.Launcher/releases to download updates manually.
     </system:String>
     <system:String x:Key="releaseNotes">Release Notes</system:String>
+    <system:String x:Key="documentation">Usage Tips:</system:String>
 
     <!--Priority Setting Dialog-->
     <system:String x:Key="priority_tips">Greater the number, the higher the result will be ranked. Try setting it as 5. If you want the results to be lower than any other plugin's, provide a negative number</system:String>

Flow.Launcher/SettingWindow.xaml

@@ -431,6 +431,7 @@
                     <RowDefinition Height="Auto" />
                     <RowDefinition Height="Auto" />
                     <RowDefinition Height="Auto" />
+                    <RowDefinition Height="Auto" />
                 </Grid.RowDefinitions>
                 <TextBlock Grid.Row="0" Grid.ColumnSpan="2" Text="{Binding ActivatedTimes, Mode=OneWay}" FontSize="12" />
                 <TextBlock Grid.Row="1" Grid.Column="0" Text="{DynamicResource website}"/>
@@ -448,7 +449,14 @@
                         <Run Text="{Binding ReleaseNotes, Mode=OneWay}" />
                     </Hyperlink>
                 </TextBlock>
-                <Button Grid.Row="4" Grid.Column="0"
+                <TextBlock Grid.Row="4" Grid.Column="0" Text="{DynamicResource documentation}" />
+                <TextBlock Grid.Row="4" Grid.Column="1">
+                    <Hyperlink NavigateUri="{Binding Documentation, Mode=OneWay}"
+                               RequestNavigate="OnRequestNavigate">
+                        <Run Text="{Binding Documentation, Mode=OneWay}" />
+                    </Hyperlink>
+                </TextBlock>
+                <Button Grid.Row="5" Grid.Column="0"
                         Content="{DynamicResource checkUpdates}" Click="OnCheckUpdates"
                         HorizontalAlignment="Left" Margin="10 30 10 10" />
             </Grid>

Flow.Launcher/ViewModel/SettingWindowViewModel.cs

@@ -454,6 +454,7 @@ public FamilyTypeface SelectedResultFontFaces
 
         public string Website => Constant.Website;
         public string ReleaseNotes => _updater.GitHubRepository +  @"/releases/latest";
+        public string Documentation => Constant.Documentation;
         public static string Version => Constant.Version;
         public string ActivatedTimes => string.Format(_translater.GetTranslation("about_activate_times"), Settings.ActivateTimes);
         #endregion