Fix lint issues

build.gradle

@@ -121,6 +121,8 @@ dependencies {
     compile 'com.nononsenseapps:filepicker:4.0.0'
     compile "com.android.support:design:${SUPPORT_VERSION}"
     compile "com.android.support:support-annotations:${SUPPORT_VERSION}"
+    compile "com.android.support:support-v13:${SUPPORT_VERSION}"
+    compile "com.android.support:cardview-v7:${SUPPORT_VERSION}"
     compile 'com.jakewharton.timber:timber:4.5.1'
     compile 'com.google.guava:guava:20.0'
     compile 'com.jakewharton:process-phoenix:1.1.1'

src/main/java/com/todoroo/astrid/ui/CheckableImageView.java

@@ -6,12 +6,12 @@
 package com.todoroo.astrid.ui;
 
 import android.content.Context;
+import android.support.v7.widget.AppCompatImageView;
 import android.util.AttributeSet;
 import android.view.ViewDebug;
 import android.widget.Checkable;
-import android.widget.ImageView;
 
-public class CheckableImageView extends ImageView implements Checkable {
+public class CheckableImageView extends AppCompatImageView implements Checkable {
 
     private static final int[] CHECKED_STATE_SET = {
         android.R.attr.state_checked

src/main/java/com/todoroo/astrid/ui/NumberPickerButton.java

@@ -6,17 +6,17 @@
 package com.todoroo.astrid.ui;
 
 import android.content.Context;
+import android.support.v7.widget.AppCompatImageButton;
 import android.util.AttributeSet;
 import android.view.KeyEvent;
 import android.view.MotionEvent;
-import android.widget.ImageButton;
 
 import org.tasks.R;
 
 /**
  * This class exists purely to cancel long click events.
  */
-public class NumberPickerButton extends ImageButton {
+public class NumberPickerButton extends AppCompatImageButton {
 
     private NumberPicker mNumberPicker;
 

src/main/java/org/tasks/ui/PriorityControlSet.java

@@ -4,6 +4,7 @@ import android.app.Activity;
 import android.content.res.ColorStateList;
 import android.os.Bundle;
 import android.support.annotation.Nullable;
+import android.support.v4.widget.CompoundButtonCompat;
 import android.support.v7.widget.AppCompatRadioButton;
 import android.view.LayoutInflater;
 import android.view.View;
@@ -124,7 +125,7 @@ public class PriorityControlSet extends TaskEditControlFragment {
 
     private void tintRadioButton(AppCompatRadioButton radioButton, int priority) {
         int color = checkBoxes.getPriorityColors().get(priority);
-        radioButton.setSupportButtonTintList(new ColorStateList(new int[][]{
+        CompoundButtonCompat.setButtonTintList(radioButton, new ColorStateList(new int[][]{
                 new int[]{-android.R.attr.state_checked}, new int[]{android.R.attr.state_checked}},
                 new int[]{color, color}));
     }