Add Linear Search in Kotlin (#4482)

* initial commit

* initial draft, all tests passed

* refined code and comments

Author: mlarsen-source

archive/k/kotlin/LinearSearch.kt

@@ -0,0 +1,28 @@
+fun main(args: Array<String>)  
+{
+    // store usage message in variable
+    val message = "Usage: please provide a list of integers (\"1, 4, 5, 11, 12\") and the integer to find (\"11\")"
+       
+    // validate input array is correct size and does not contain empty Strings 
+    if(args.size !=2 || args[0].isBlank() || args[1].isBlank())
+    {
+        println(message)
+        return
+    } 
+    
+    // convert input number String into a List of integers, invalid characters are converted to null
+    val intList = args[0].split(",").map { it.trim().toIntOrNull() }
+ 
+    // convert input key String into an int, invalid characters are converted to null
+    val key = args[1].toIntOrNull()
+ 
+    // check if the List or the key contains null (invalid) elements
+    if(null in intList || key == null)
+    {
+        println(message)
+        return
+    }
+
+    // check if key is in the List and print returned boolean   
+    println(key in intList)
+}