Intentions: Implement "Introduce local variable" intention

#KT-11768 Fixed

idea/testData/intentions/introduceVariable/.intention

@@ -0,0 +1 @@
+org.jetbrains.kotlin.idea.intentions.IntroduceVariableIntention

idea/testData/intentions/introduceVariable/afterExpression.kt

@@ -0,0 +1,5 @@
+fun foo(a: Int, b: Int) = a + b
+
+fun foo() {
+    foo(1 + 2, 3 * 4) <caret>//
+}

idea/testData/intentions/introduceVariable/afterExpression.kt.after

@@ -0,0 +1,5 @@
+fun foo(a: Int, b: Int) = a + b
+
+fun foo() {
+    val foo = foo(1 + 2, 3 * 4)<caret> //
+}

idea/testData/intentions/introduceVariable/atExpressionEnd.kt

@@ -0,0 +1,5 @@
+fun foo(a: Int, b: Int) = a + b
+
+fun foo() {
+    foo(1 + 2, 3 * 4)<caret>
+}

idea/testData/intentions/introduceVariable/atExpressionEnd.kt.after

@@ -0,0 +1,5 @@
+fun foo(a: Int, b: Int) = a + b
+
+fun foo() {
+    val foo = foo(1 + 2, 3 * 4)<caret>
+}

idea/testData/intentions/introduceVariable/atExpressionStart.kt

@@ -0,0 +1,5 @@
+fun foo(a: Int, b: Int) = a + b
+
+fun foo() {
+    <caret>foo(1 + 2, 3 * 4)
+}

idea/testData/intentions/introduceVariable/atExpressionStart.kt.after

@@ -0,0 +1,5 @@
+fun foo(a: Int, b: Int) = a + b
+
+fun foo() {
+    val foo = foo(1 + 2, 3 * 4)<caret>
+}

idea/testData/intentions/introduceVariable/atNestedExpression.kt

@@ -0,0 +1,5 @@
+fun foo(a: Int, b: Int) = a + b
+
+fun foo() {
+    foo(1 <caret>+ 2, 3 * 4)
+}

idea/testData/intentions/introduceVariable/atNestedExpression.kt.after

@@ -0,0 +1,5 @@
+fun foo(a: Int, b: Int) = a + b
+
+fun foo() {
+    val foo = foo(1 + 2, 3 * 4)<caret>
+}

idea/testData/intentions/introduceVariable/beforeExpression.kt

@@ -0,0 +1,6 @@
+// IS_APPLICABLE: false
+fun foo(a: Int, b: Int) = a + b
+
+fun foo() {
+   <caret> foo(1 + 2, 3 * 4)
+}

idea/testData/intentions/introduceVariable/noType.kt

@@ -0,0 +1,6 @@
+// IS_APPLICABLE: false
+fun foo(a: Int, b: Int) = a + b
+
+fun foo() {
+   val foo = foo(1 + 2, 3 * 4)<caret>
+}

idea/testData/intentions/introduceVariable/nothingType.kt

@@ -0,0 +1,4 @@
+// IS_APPLICABLE: false
+fun foo(): Int {
+   return 1 + 2<caret>
+}

idea/testData/intentions/introduceVariable/unitType.kt

@@ -0,0 +1,6 @@
+// IS_APPLICABLE: false
+fun foo(a: Int, b: Int) {}
+
+fun foo() {
+   foo(1 + 2, 3 * 4)<caret>
+}