Add documents to explain a function

Add documents to add a new function

docs/user/add-new-function.md

@@ -0,0 +1,51 @@
+# Add a new function
+
+This documentation will tell you on how to add a new function to the application. If you are unsure what a function is check out the [what is a function][what-is-a-function] documentation.
+
+To add a new function click on `File->New Function` while being in the main window. This will open up the add function screen
+
+![add-a-function]
+
+Provide display name for the function, this will be shown on the button. The name needs to be 5 - 25 chars. If you want add an description, this will be shown as a tooltip if you hover over the button later on.
+
+![select-plugin]
+
+Select the plugin to start the application or binary. Checkout the [plugin overview][available-plugins] for more information.
+
+![additional-settings]
+
+Select the setting specific for this function. For more information about the [setting scope][setting-scope] check the documentation.
+
+If required enter any function parameters, those are arguments which are getting parsed to the script or application.
+
+Select the path to the script or application to start. To do so press the `...` next to the text field
+
+![final-function]
+
+If everything is entered as expected, press the `Ok` button. If the button is still grayed out something is wrong or could not be found.
+
+The function will now be shown in the main view like this.
+
+![function-in-tool]
+
+Showing the tooltip on hover
+
+![function-in-tool-tooltip]
+
+Press the button you created to start the tool. If this is not working you will need to check the log file for further information.
+
+## User Manual
+
+Go back to the [user manual][back]
+
+[back]: user-manual.md
+[what-is-a-function]: ./what-is-a-function.md
+[available-plugins]: ./plugin-overview.md
+[setting-scope]: ./scope-of-a-setting.md
+[main-window]: https://i.imgur.com/oswayay.png
+[add-a-function]: https://i.imgur.com/mr3Folx.png
+[select-plugin]: https://i.imgur.com/8ITUSA3.png
+[additional-settings]: https://i.imgur.com/O8va6Gd.png
+[final-function]: https://i.imgur.com/lmiIzjX.png
+[function-in-tool]: https://i.imgur.com/60cHafm.png
+[function-in-tool-tooltip]: https://i.imgur.com/8lUHaiU.png

docs/user/user-manual.md

@@ -5,11 +5,15 @@ The manual of the application. This page does list all the things you as a user
 - [[1] Installation][installation]
 - [[2] Plugin Overview][plugin-overview]
 - [[3] Languages][language]
+- [[4] Add a function][add-a-function]
+  - [[4a] What is a function][what-is-a-function]
 - [[4] Scope of a Setting][scope-of-a-setting]
 - [[5] Hotkeys][hotkey-overview]
 
 [installation]: ./installation.md
 [language]: ./languages.md
 [scope-of-a-setting]: ./scope-of-a-setting.md
+[add-a-function]: ./add-new-function.md
+[what-is-a-function]: ./what-is-a-function.md
 [plugin-overview]: ./plugin-overview.md
 [hotkey-overview]: ./hotkey-overview.md

docs/user/what-is-a-function.md

@@ -0,0 +1,15 @@
+# What is a function
+
+The term function in connection with the `Modular Tool Manager` is a set of data required to start a specific application or script. Those functions are displayed as buttons on the main window
+
+![main-window]
+
+`My test function` is a function which will start a specific application or script.
+
+## User Manual
+
+Go back to the [user manual][back]
+
+[back]: user-manual.md
+
+[main-window]: https://i.imgur.com/oswayay.png