added second parameter for installDevonfwIde in documentation

Author: GuentherJulian

documentation/Functions.md

@@ -7,11 +7,12 @@ The following functions are already implemented:
 
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-### installDevonIde
+### installDevonfwIde
 #### parameter
 1. The tools you want to install within the devonfw ide: string array
+2. Optional: The version of the ide to install
 #### example
-installDevonfwIde(["java","mvn"])
+installDevonfwIde(["java","mvn"], "2020.08.001")
 
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