Add local maven version debug builds

[theosirian]

Adds a debug publication that can be used to generate a local maven artifact.
It requires that mvn be installed, for instance, in MacOS with Homebrew, it would be brew install maven.

VERSION=0.0.32-local ./gradlew publishDebugPublicationToMavenLocal

To use this publication with other projects, it's necessary to add mavenLocal() to its repositories:

--- a/android/build.gradle
+++ b/android/build.gradle
@@ -19,6 +19,7 @@ buildscript {
    repositories {
        google()
        mavenCentral()
+        mavenLocal()
    }

    dependencies {
@@ -36,6 +37,7 @@ allprojects {
    repositories {
        google()
        mavenCentral()
+        mavenLocal()
    }
}