How to get a report with all sub-projects dependencies licenses?

Hi,
I have to list my project dependencies licenses for legal issues, and I’m looking for a tool/plugin to do it automatically.
I’ve looked at “project-report” plugin, but I’ve some difficulties to use it and I’m not sure it will do the work.
Do you have some ideas of plugins I can use for it? Here is my build.gradle file, just in case:

ext.MyScriptEngineVersion = "7.3.6"
ext.SpringBootVersion = "1.3.6.RELEASE"
ext.SpringFrameworkVersion = "4.2.6.RELEASE"
ext.SpringSecurityVersion = "4.1.0.RELEASE"
ext.ServletApiVersion = "3.1.0"
ext.JstlVersion = "1.2"
ext.SpringDataVersion = "1.8.4.RELEASE"
ext.MongoDriverVersion = "3.2.2"
ext.AspectjVersion = "1.8.9"
ext.JacksonVersion = "2.3.0"
ext.Log4jVersion = "1.2.17"
ext.Slf4jVersion = "1.7.12"
ext.JavaDocPluginVersion = "2.7"
ext.JUnitVersion = "4.11"

ext.JavaMailVersion = "1.4.1"
ext.CommonsLoggingVersion = "1.1.1"
ext.CommonsLangVersion = "2.6"
ext.CommonsCollectionsVersion = "3.2.2"
ext.Recaptcha4jVersion = "0.0.7"
ext.CommonsDigesterVersion = "1.8.1"
ext.CommonsCodecVersion = "1.4"
ext.CommonsIOVersion = "2.4"
ext.CommonsValidatorVersion = "1.5.1"
ext.CommonsHttpclientVersion = "3.1"
ext.CommonsFileUploadVersion = "1.3"
ext.HttpComponentHttpclientVersion = "4.2.5"
ext.CommonsCliVersion = "1.3.1"

ext.CollectionsGenericVersion = "4.01"
ext.SelmaVersion = "0.15"
ext.Stringtemplate = "4.0.2"
ext.SardineVersion = "5.0.3"
ext.BouncyCastleVersion = "1.46"
ext.ProGuardVersion = "5.2.1"
ext.JodatimeVersion = "2.3"
ext.Sqlite4JavaVersion = "0.282"
ext.Jsr250APIVersion = "1.0"
ext.WebSocketVersion = "1.0"
ext.GeoIpVersion = "1.3.1"


buildscript {
    repositories {
        mavenLocal()
        mavenCentral()
        jcenter()
    }
    dependencies {
            classpath("org.springframework.boot:spring-boot-gradle-plugin:1.3.6.RELEASE")
    }
  }


allprojects {

}


apply plugin: 'spring-boot'
apply plugin: 'project-report'

dependencyReport {
    projects = project.allprojects
    outputFile = null
}
subprojects {
    apply plugin: 'java'
    apply plugin: 'idea'

    sourceCompatibility = JavaVersion.VERSION_1_8
    targetCompatibility = JavaVersion.VERSION_1_8

    repositories {
        mavenLocal()
        mavenCentral()
    }

    dependencies {
    }

    version = '3.2'

    jar {
        manifest.attributes provider: 'gradle'
    }

    idea {
        module {
            downloadJavadoc = true
            downloadSources = true
        }
    }

}

I am also interested in this. The best that I have seen so far is some simple scripts that scrape jar files for LICENSE files or pom.xml’s for blocks.