Migrated library to modern Gradle + JitPack support, fixed Kotlin conflicts & deprecated configurations

[Shivgupta1031]

📌 Overview

This pull request updates the project to work with modern Android tooling and JitPack publishing.
It removes deprecated Bintray/JCenter dependencies, fixes Kotlin version conflicts, and makes the library compatible with Gradle 8, Java 17, and AGP 7+.

✅ Key Changes
⚙️ Build System Modernization

✅ Migrated from Bintray/JCenter (deprecated) to JitPack + Maven Publish

✅ Updated gradle-wrapper to Gradle 7.5+ / 8.x

✅ Updated Android Gradle Plugin to 7.4.2

✅ Switched to Java 17 (required by AGP 8 and Android SDK 35)

✅ Removed old dependencies:

com.jfrog.bintray.gradle:gradle-bintray-plugin

jcenter()

com.github.dcendents:android-maven-gradle-plugin

🛠 Kotlin Compatibility Fixes

✅ Unified Kotlin version to 1.8.22 across all modules

✅ Removed conflicting kotlin-stdlib-jdk7/jdk8:1.6.21

✅ Enforced Kotlin version via Gradle resolution strategies

✅ Added org.jetbrains.kotlin.android plugin properly

📦 Publishing Support (JitPack Ready)

✅ Configured maven-publish plugin in library module

✅ Generates .aar, .pom, and -sources.jar artifacts

✅ Group & Artifact ID defined:

groupId = com.github.Shivgupta1031
artifactId = Android-Image-Slider
version = 1.4.4

✅ Can now be used via:

implementation "com.github.Shivgupta1031:Android-Image-Slider:1.4.4"

🗑 Deprecated / Removed Items

❌ Removed Bintray upload scripts (bintray.gradle, install.gradle)

❌ Removed jcenter() repositories

❌ Removed old versioning inside ext { ... } blocks

❌ Removed unnecessary kotlin-stdlib manual imports

📁 Project Structure is Now:
/autoimageslider → Library module (publish-ready)
/app → Sample app (unchanged)
/build.gradle → Cleaned and updated
/settings.gradle → Modern dependency resolution added
/jitpack.yml → Java 17 setup for JitPack builds

✅ Result

✔ Library builds successfully on local and JitPack
✔ No more Kotlin duplicate class conflicts
✔ Compatible with Android 14 (API 35)
✔ This fork can now be used directly as a dependency by anyone

🙌 Suggestions / Future Improvements

✅ Publish to Maven Central for wider availability

✅ Add GitHub Actions for auto-release on new tag

✅ Add README setup instructions for developers

✅ Migrate sample app to Kotlin or Jetpack Compose (optional)