Add a project for a cli application and update dependencies

cli/build.gradle

@@ -0,0 +1,6 @@
+apply plugin: 'java-library'
+
+dependencies {
+    implementation fileTree(dir: 'libs', include: ['*.jar'])
+    compile "com.beust:jcommander:1.71"
+}

cli/src/main/java/me/impy/aegis/cli/Main.java

@@ -0,0 +1,7 @@
+package me.impy.aegis.cli;
+
+public class Main {
+    public static void main(String[] args) {
+
+    }
+}