Change minSdkVersion to 15, update support library

Author: hanihashemi

app/build.gradle

@@ -24,7 +24,7 @@ android {
 
 dependencies {
     implementation fileTree(dir: 'libs', include: ['*.jar'])
-    implementation 'com.android.support:appcompat-v7:27.0.2'
+    implementation 'com.android.support:appcompat-v7:27.1.1'
     implementation 'com.android.support.constraint:constraint-layout:1.0.2'
     testImplementation 'junit:junit:4.12'
     androidTestImplementation 'com.android.support.test:runner:1.0.1'

collapsiblecalendarview2/build.gradle

@@ -5,10 +5,8 @@ group = 'com.github.shrikanth7698'
 android {
     compileSdkVersion 27
 
-
-
     defaultConfig {
-        minSdkVersion 21
+        minSdkVersion 15
         targetSdkVersion 27
         versionCode 1
         versionName "1.0"
@@ -26,13 +24,12 @@ android {
             proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
         }
     }
-
 }
 
 dependencies {
     implementation fileTree(dir: 'libs', include: ['*.jar'])
 
-    implementation 'com.android.support:appcompat-v7:27.0.2'
+    implementation 'com.android.support:appcompat-v7:27.1.1'
     testImplementation 'junit:junit:4.12'
     androidTestImplementation 'com.android.support.test:runner:1.0.1'
     androidTestImplementation 'com.android.support.test.espresso:espresso-core:3.0.1'