Implement "Safe Delete" refactoring for named functions

Conflicts:
	idea/src/org/jetbrains/jet/plugin/refactoring/safeDelete/KotlinSafeDeleteProcessor.java

idea/testData/safeDelete/deleteFunction/fun1.kt

@@ -0,0 +1,11 @@
+package test
+
+import test.foo
+
+fun <caret>foo() {
+
+}
+
+class B {
+
+}

idea/testData/safeDelete/deleteFunction/fun1.kt.after

@@ -0,0 +1,5 @@
+package test
+
+class B {
+
+}

idea/testData/safeDelete/deleteFunction/fun2.kt

@@ -0,0 +1,11 @@
+package test
+
+import test.foo
+
+fun <caret>foo() {
+
+}
+
+class B {
+    val ref = ::foo
+}

idea/testData/safeDelete/deleteFunction/fun2.kt.messages

@@ -0,0 +1,2 @@
+Function foo has 1 usage that is not safe to delete.
+Of those 0 usages are in strings, comments, or non-code files.

idea/testData/safeDelete/deleteFunction/implement1.kt

@@ -0,0 +1,9 @@
+trait A {
+    fun foo()
+}
+
+class B: A {
+    override fun <caret>foo() {
+
+    }
+}

idea/testData/safeDelete/deleteFunction/implement1.kt.messages

@@ -0,0 +1 @@
+fun foo(): jet.Unit in final class B : A implements fun foo(): jet.Unit in trait A.

idea/testData/safeDelete/deleteFunction/implement2.kt

@@ -0,0 +1,13 @@
+trait A {
+    fun foo()
+}
+
+trait Z {
+    fun foo()
+}
+
+class B: A, Z {
+    override fun <caret>foo() {
+
+    }
+}

idea/testData/safeDelete/deleteFunction/implement2.kt.messages

@@ -0,0 +1,2 @@
+fun foo(): jet.Unit in final class B : A, Z implements fun foo(): jet.Unit in trait A.
+fun foo(): jet.Unit in final class B : A, Z implements fun foo(): jet.Unit in trait Z.

idea/testData/safeDelete/deleteFunction/noUsages.kt

@@ -0,0 +1,7 @@
+class C {
+    fun <caret>foo {
+    }
+}
+
+class B {
+}

idea/testData/safeDelete/deleteFunction/noUsages.kt.after

@@ -0,0 +1,5 @@
+class C {
+}
+
+class B {
+}

idea/testData/safeDelete/deleteFunction/override1.kt

@@ -0,0 +1,11 @@
+open class A {
+    open fun foo() {
+
+    }
+}
+
+class B: A {
+    override fun <caret>foo() {
+
+    }
+}

idea/testData/safeDelete/deleteFunction/override1.kt.after

@@ -0,0 +1,8 @@
+open class A {
+    open fun foo() {
+
+    }
+}
+
+class B: A {
+}

idea/testData/safeDelete/deleteFunction/override2.kt

@@ -0,0 +1,11 @@
+open class A {
+    open fun <caret>foo() {
+
+    }
+}
+
+class B: A {
+    override fun foo() {
+
+    }
+}

idea/testData/safeDelete/deleteFunction/override2.kt.after

@@ -0,0 +1,5 @@
+open class A {
+}
+
+class B: A {
+}

idea/testData/safeDelete/deleteFunction/overrideAndImplement1.kt

@@ -0,0 +1,15 @@
+open class A {
+    open fun foo() {
+
+    }
+}
+
+trait Z {
+    fun foo()
+}
+
+class B: A, Z {
+    override fun <caret>foo() {
+
+    }
+}

idea/testData/safeDelete/deleteFunction/overrideAndImplement1.kt.messages

@@ -0,0 +1 @@
+fun foo(): jet.Unit in final class B : A, Z implements fun foo(): jet.Unit in trait Z.

idea/testData/safeDelete/deleteFunction/overrideAndImplement2.kt

@@ -0,0 +1,15 @@
+open class A {
+    open fun <caret>foo() {
+
+    }
+}
+
+trait Z {
+    fun foo()
+}
+
+class B: A, Z {
+    override fun foo() {
+
+    }
+}

idea/testData/safeDelete/deleteFunction/overrideAndImplement2.kt.after

@@ -0,0 +1,12 @@
+open class A {
+}
+
+trait Z {
+    fun foo()
+}
+
+class B: A, Z {
+    override fun foo() {
+
+    }
+}

idea/testData/safeDelete/deleteFunction/overrideWithUsages.kt

@@ -0,0 +1,15 @@
+open class A {
+    open fun <caret>foo() {
+
+    }
+}
+
+class B: A {
+    fun bar() {
+        foo()
+    }
+
+    override fun foo() {
+
+    }
+}

idea/testData/safeDelete/deleteFunction/overrideWithUsages.kt.after

@@ -0,0 +1,12 @@
+open class A {
+}
+
+class B: A {
+    fun bar() {
+        foo()
+    }
+
+    fun foo() {
+
+    }
+}