Upgrade dependencies and update used JDKs (#16)

* Remove unsupported JDK versions

* Update Gradle to version 4.4

* Disable ECDSA algorithm

* Run before install

* Fix deprication error for left shift operator

The error in question was:
> The Task.leftShift(Closure) method has been deprecated and is scheduled to be
> removed in Gradle 5.0. Please use Task.doLast(Action) instead.

* Remove Java 6 tests but compile with support for Java 6

Gradle has problem downloading dependencies:
https://travis-ci.org/tus/tus-java-client/jobs/318341024#L505

* Update mockserver-netty

* Use sudo for changing Java security file

* Add comment

Author: Acconut

.travis.yml

@@ -1,21 +1,25 @@
-sudo: false
+sudo: required
 language: java
 jdk:
 - oraclejdk8
-- oraclejdk7
-- openjdk6
+- oraclejdk9
 - openjdk7
+- openjdk8
+before_install:
+  # OpenJDK 7 does not support HTTPS using Elliptic Curves, but the Gradle
+  # server use them. Therefore, we manually disable them to enable communication.
+  - sudo sed -i 's/^jdk.certpath.disabledAlgorithms=.*/jdk.certpath.disabledAlgorithms=MD2, MD5, RSA keySize < 1024, ECDSA/' /usr/lib/jvm/java-7-openjdk-amd64/jre/lib/security/java.security || true
 deploy:
   - provider: script
     script: ./deploy-gh-pages.sh
     on:
       branch: master
-      jdk: openjdk7
+      jdk: openjdk8
   - provider: script
     script: ./deploy-bintray.sh
     on:
       tags: true
-      jdk: openjdk6
+      jdk: openjdk8
 
 env:
   global:

build.gradle

@@ -9,10 +9,15 @@ allprojects {
     }
 }
 
+// We compile the library using Java 1.6 compatibility
+// in order to ensure interoperability with older Android platforms.
+sourceCompatibility = 1.6
+targetCompatibility = 1.6
+
 dependencies {
     compile 'org.jetbrains:annotations:13.0'
     testCompile 'junit:junit:4.12'
-    testCompile 'org.mock-server:mockserver-netty:3.9.17'
+    testCompile 'org.mock-server:mockserver-netty:5.2.2'
 }
 
 task sourcesJar(type: Jar, dependsOn: classes) {
@@ -25,38 +30,40 @@ task javadocJar(type: Jar, dependsOn: javadoc) {
     from javadoc.destinationDir
 }
 
-task createPom << {
-    pom {
-        project {
-            groupId 'io.tus.java.client'
-            artifactId 'tus-java-client'
-            name 'tus-java-client'
-            version project.getProperties().get('pomVersion')
-            packaging 'pom'
-            description 'Java client for tus, the resumable file uploading protocol.'
-            url 'http://tus.io'
-
-            scm {
-                url 'https://github.com/tus/tus-java-client'
-                connection 'https://github.com/tus/tus-java-client'
-                developerConnection 'https://github.com/tus/tus-java-client'
-            }
+task createPom {
+    doLast {
+        pom {
+            project {
+                groupId 'io.tus.java.client'
+                artifactId 'tus-java-client'
+                name 'tus-java-client'
+                version project.getProperties().get('pomVersion')
+                packaging 'pom'
+                description 'Java client for tus, the resumable file uploading protocol.'
+                url 'http://tus.io'
 
-            developers {
-                developer {
-                    id 'acconut'
-                    name 'Marius Kleidl'
-                    email '[email protected]'
+                scm {
+                    url 'https://github.com/tus/tus-java-client'
+                    connection 'https://github.com/tus/tus-java-client'
+                    developerConnection 'https://github.com/tus/tus-java-client'
                 }
-            }
 
-            inceptionYear '2015'
-            licenses {
-                license {
-                    name 'The MIT License (MIT)'
-                    url 'http://opensource.org/licenses/MIT'
+                developers {
+                    developer {
+                        id 'acconut'
+                        name 'Marius Kleidl'
+                        email '[email protected]'
+                    }
+                }
+
+                inceptionYear '2015'
+                licenses {
+                    license {
+                        name 'The MIT License (MIT)'
+                        url 'http://opensource.org/licenses/MIT'
+                    }
                 }
             }
-        }
-    }.writeTo("build/libs/pom.xml")
+        }.writeTo("build/libs/pom.xml")
+    }
 }

gradle/wrapper/gradle-wrapper.jar

@@ -1,6 +1,5 @@
-#Thu Jul 16 22:37:16 CEST 2015
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-1.12-all.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-4.4-bin.zip