Error Synchronizing the gradle on Android

Well my problem that I have now is that I just imported boostrap in my Android application, in my opinion I have imported it correctly but I got this error, which I have not been able to solve yet.

The error I get is the following: No such property: GROUP for class: org.gradle.api.publication.maven.internal.ant.DefaultGroovyMavenDeployer

Here is the Build.gradle Code (Module app):

apply plugin: 'com.android.application'

    android {
        compileSdkVersion 23
        buildToolsVersion "23.0.3"

        defaultConfig {
            applicationId "onbus.garay.david.onbus"
            minSdkVersion 15
            targetSdkVersion 23
            versionCode 1
            versionName "1.0"
        }
        buildTypes {
            release {
                minifyEnabled false
                proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
            }
        }
    }

    dependencies {
        compile fileTree(dir: 'libs', include: ['*.jar'])
        testCompile 'junit:junit:4.12'
        compile 'com.android.support:appcompat-v7:23.4.0'
    }

Here is the build.gradle code (Module OnBus):

// Top-level build file where you can add configuration options common to all sub-projects/modules.

buildscript {
    repositories {
        jcenter()
    }
    dependencies {
        classpath 'com.android.tools.build:gradle:2.1.0'

        // NOTE: Do not place your application dependencies here; they belong
        // in the individual module build.gradle files
    }
}

allprojects {
    repositories {
        jcenter()
    }
}

task clean(type: Delete) {
    delete rootProject.buildDir
}

Here is the Boostrap.gradle code:

apply plugin: 'com.android.library'
apply from: 'push.gradle'

android {
    compileSdkVersion 23
    buildToolsVersion "23.0.3"

    defaultConfig {
        minSdkVersion 14
        targetSdkVersion 23
        versionCode = 1
        versionName = 1.0
    }
}

dependencies {
    compile 'com.android.support:support-annotations:23.3.0'
    compile 'com.android.support:support-v4:23.3.0'
}