Add instructions to quickly test changes in the extractor

- Make use of the local Maven repository

README.md

@@ -13,6 +13,17 @@ If you're using Gradle, you could add NewPipe Extractor as a dependency with the
 1. Add `maven { url 'https://jitpack.io' }` to the `repositories` in your `build.gradle`.
 2. Add `compile 'com.github.TeamNewPipe:NewPipeExtractor:v0.11.0'`the `dependencies` in your `build.gradle`. Replace `v0.11.0` with the latest release.
 
+### Testing changes
+
+To test changes quickly you can build the library locally. Using the local Maven repository is a good approach, here's a gist of how to use it:
+
+1. Add `mavenLocal()` in your project `repositories` list (usually as the first entry to give priority above the others).
+2. It's _recommended_ that you change the `version` of this library (e.g. `LOCAL_SNAPSHOT`).
+3. Run gradle's `ìnstall` task to deploy this library to your local repository (using the wrapper, present in the root of this project: `./gradlew install`)
+4. Change the dependency version used in your project to match the one you chose in step 2 (`implementation 'com.github.TeamNewPipe:NewPipeExtractor:LOCAL_SNAPSHOT'`)
+
+> Tip for Android Studio users: After you make changes and run the `install` task, use the menu option `File → "Sync with File System"` to refresh the library in your project.
+
 ## Supported sites
 
 The following sites are currently supported:

build.gradle

@@ -1,15 +1,23 @@
 allprojects {
     apply plugin: 'java-library'
+    apply plugin: 'maven'
+
     sourceCompatibility = 1.7
     targetCompatibility = 1.7
 
     version 'v0.13.0'
+    group 'com.github.TeamNewPipe'
 
     repositories {
         jcenter()
     }
 }
 
+dependencies {
+    implementation project(':extractor')
+    implementation project(':timeago-parser')
+}
+
 subprojects {
     task sourcesJar(type: Jar, dependsOn: classes) {
         classifier = 'sources'