chore(examples): clean up

Author: AlexanderPrendota

examples/01_introduction/02_Null Safety.md

@@ -5,7 +5,6 @@ In an effort to rid the world of `NullPointerException`, variable types in Kotli
 <div class="language-kotlin" theme="idea">
 
 ```kotlin
-//sampleStart
 fun main() {
     var neverNull: String = "This can't be null"            // 1
 
@@ -16,7 +15,6 @@ fun main() {
     var inferredNonNull = "The compiler assumes non-null"   // 4
 
 }
-//sampleEnd
 ```
 
 </div>

examples/02_control_structures/02_Loops.md

@@ -24,7 +24,6 @@ fun main() {
 <div class="language-kotlin" theme="idea">
 
 ```kotlin
-//sampleStart
 fun eatACake() = println("Eat a Cake")
 fun bakeACake() = println("Bake a Cake")
 
@@ -43,7 +42,6 @@ fun main() {
     } while (cakesBaked < cakesEaten)
 
 }
-//sampleEnd
 ```
 
 </div>

examples/03_declarations/04_Inheritance.md

@@ -37,7 +37,6 @@ fun main() {
 <div class="language-kotlin" theme="idea">
 
 ```kotlin
-//sampleStart
 open class Tiger(val origin: String) {
     fun sayHello() {
         println("A tiger from $origin says: grrhhh!")
@@ -50,7 +49,6 @@ fun main() {
     val tiger: Tiger = SiberianTiger()
     tiger.sayHello()
 }
-//sampleEnd
 ```
 
 </div>

examples/04_functional/01_Higher-Order Functions.md

@@ -35,7 +35,6 @@ that itself takes two parameters of type integer and returns an integer.
 <div class="language-kotlin" theme="idea">
 
 ```kotlin
-//sampleStart
 fun operation(): (Int) -> Int {                                     // 1
     return ::square
 }
@@ -47,7 +46,6 @@ fun main() {
     val func = operation()                                          // 3
     println(func(2))                                                // 4
 }
-//sampleEnd
 ```
 
 </div>

examples/05_special_classes/04_Object.md

@@ -48,7 +48,6 @@ Object like that, is often used like anonymous class in Java.
 <div class="language-kotlin" theme="idea">
 
 ```kotlin
-//sampleStart
 fun rentPrice(standardDays: Int, festivityDays: Int, specialDays: Int): Unit {  //1
 
     val dayRates = object {                                                     //2
@@ -67,7 +66,6 @@ fun rentPrice(standardDays: Int, festivityDays: Int, specialDays: Int): Unit {
 fun main(){
     rentPrice(10, 2, 1)                                                         //5
 }
-//sampleEnd
 ```
 
 </div>