[Docs] Added Microsoft.Plugin.Sys DevDoc (#8350)

* Added Initial Microsoft.Plugin.Sys DevDoc

* Reword

* Updated Links within Readme

* Corrected Case for URL

doc/devdocs/modules/launcher/plugins/sys.md

@@ -0,0 +1,23 @@
+# Sys Plugin
+
+As the name suggests, the Sys Plugin is used to directly run Windows system commands that have been entered by the user as a query. This is done by parsing the entry and validating the command, followed by executing it.
+
+* Shutdown
+* Restart
+* Sign Out
+* Lock
+* Sleep
+* Hibernate
+* Empty Recycle Bin
+
+![Image of Sys plugin](/doc/images/launcher/plugins/sys.gif)
+
+## [`Sys`](/src/modules/launcher/Plugins/Microsoft.Plugin.Sys/Main.cs)
+
+* Tries to parse the user input and returns a specific Windows system command by using a [`Result`](/src/modules/launcher/Wox.Plugin/Result.cs) list.
+
+* While parsing, the Sys plugin uses [`FuzzyMatch`](/src/modules/launcher/Wox.Infrastructure/StringMatcher.cs) to get characters matching a result in the list.
+
+### Score
+
+* [`CalculateSearchScore`](/src/modules/launcher/Wox.Infrastructure/StringMatcher.cs) A match found near the beginning of a string is scored more than a match found near the end. A match is scored more if the characters in the patterns are closer to each other, while the score is lower if they are more spread out.

doc/devdocs/modules/launcher/readme.md

@@ -10,5 +10,6 @@
     - [Indexer](/doc/devdocs/modules/launcher/plugins/indexer.md)
     - [Program](/doc/devdocs/modules/launcher/plugins/program.md)
     - [Shell](/doc/devdocs/modules/launcher/plugins/shell.md)
+    - [Sys](/doc/devdocs/modules/launcher/plugins/sys.md)
     - [Uri](/doc/devdocs/modules/launcher/plugins/uri.md)
     - [Window Walker](/doc/devdocs/modules/launcher/plugins/windowwalker.md)