Add uberjar (#51)

* Add uber jar for "auto" to include all of its dependencies in Maven artifact

Author: zoercai

build.gradle

@@ -14,7 +14,7 @@ subprojects {
         mavenCentral()
         mavenLocal()
         maven { url 'https://oss.jfrog.org/artifactory/oss-snapshot-local' }
-        maven { url 'https://dl.bintray.com/open-telemetry/maven'}
+        maven { url 'https://dl.bintray.com/open-telemetry/maven' }
     }
 
     ext {
@@ -27,7 +27,7 @@ subprojects {
         openTelemetryInstrumentationVersion = '0.9.0'
         junitVersion = '4.13'
         mockitoVersion = '3.5.10'
-        opentelemetryOperationsVersion = "0.9.1"  // CURRENT_RELEASE_VERSION
+        opentelemetryOperationsVersion = '0.9.1'  // CURRENT_RELEASE_VERSION
 
         libraries = [
                 auto_service_annotations     : "com.google.auto.service:auto-service-annotations:${autoServiceVersion}",

exporters/auto/build.gradle

@@ -14,3 +14,11 @@ dependencies {
     implementation(project(':exporter-metrics'))
     implementation(project(':exporter-trace'))
 }
+
+jar.enabled = false
+
+tasks.build.dependsOn tasks.shadowJar
+
+shadowJar{
+    classifier = null
+}