Hint for upgrading Android SDK to 2.8.1

[martyzz1]

Have spent a bit of time on this, and managed to do the upgrade.
As our fork is not easily mergeable to this original, I can't raise a pull request, but wanted to share as it was a little fiddly

diff --git a/opentok-cordova/plugin.xml b/opentok-cordova/plugin.xml
index d8a3b42..383f721 100644
--- a/opentok-cordova/plugin.xml
+++ b/opentok-cordova/plugin.xml
@@ -12,6 +12,7 @@
     <keywords>opentok,tokbox</keywords>

     <platform name="android">
+      <framework src="build-extras.gradle" custom="true" type="gradleReference" />
       <asset src="www/opentok-cordova.js" target="opentok-cordova.js" />

       <source-file src="src/android/pawsquad/OpenTokCordova.java"
@@ -28,10 +29,7 @@
       </config-file>

       <!-- copy opentok sdk -->
-      <source-file src="src/android/libs/opentok-android-sdk-2.7.0.jar" target-dir="libs/" />
-      <source-file src="src/android/libs/armeabi/libopentok.so" target-dir="libs/armeabi" />
-      <source-file src="src/android/libs/armeabi-v7a/libopentok.so" target-dir="libs/armeabi-v7a" />
-      <source-file src="src/android/libs/x86/libopentok.so" target-dir="libs/x86" />
+      <source-file src="src/android/libs/opentok-android-sdk-2.8.1.aar" target-dir="libs/" />

       <config-file target="config.xml" parent="/*">
         <feature name="OpenTokPlugin">

diff --git a/opentok-cordova/src/android/libs/armeabi-v7a/libopentok.so b/opentok-cordova/src/android/libs/armeabi-v7a/libopentok.so
deleted file mode 100755
index f5d2b15..0000000
Binary files a/opentok-cordova/src/android/libs/armeabi-v7a/libopentok.so and /dev/null differ
diff --git a/opentok-cordova/src/android/libs/armeabi/libopentok.so b/opentok-cordova/src/android/libs/armeabi/libopentok.so
deleted file mode 100755
index 8112b9b..0000000
Binary files a/opentok-cordova/src/android/libs/armeabi/libopentok.so and /dev/null differ
diff --git a/opentok-cordova/src/android/libs/x86/libopentok.so b/opentok-cordova/src/android/libs/x86/libopentok.so
deleted file mode 100755
index c27d174..0000000
Binary files a/opentok-cordova/src/android/libs/x86/libopentok.so and /dev/null 

And also Added a new file:-

diff --git a/opentok-cordova/build-extra.gradle b/opentok-cordova/build-extras.gradle
new file mode 100644
index 0000000..96c4732
--- /dev/null
+++ b/opentok-cordova/build-extras.gradle
@@ -0,0 +1,43 @@
+apply plugin: 'com.android.application'
+
+buildscript {
+    repositories {
+        jcenter()
+    }
+    dependencies {
+        classpath 'com.android.tools.build:gradle:1.0.0'
+    }
+}
+
+allprojects {
+    repositories {
+        jcenter()
+        maven {
+            url  "http://tokbox.bintray.com/maven"
+        }
+    }
+}
+
+
+
+dependencies {
+    compile fileTree(dir: 'libs', include: ['*.jar'])
+    compile 'com.opentok.android:opentok-android-sdk:2.8.1+'
+    compile 'com.android.support:appcompat-v7:23.1.0'
+    compile 'com.android.support:design:23.0.0'
+}