Fix check for Gradle version

In case Gradle's version is with three numbers ("2.2.3" for example), our
current check is failing and makes the doctor command unusable. Compare
current gradle version with min required one only after they are in the
same format.

Author: rosen-vladimirov

lib/common

@@ -66,7 +66,7 @@ class DoctorService implements IDoctorService {
 			result = true;
 		}
 
-		if(sysInfo.gradleVer && helpers.versionCompare(sysInfo.gradleVer, DoctorService.MIN_SUPPORTED_GRADLE_VERSION) === -1) {
+		if(sysInfo.gradleVer && !this.isGradleVersionSupported(sysInfo.gradleVer)) {
 			this.$logger.warn(`WARNING: Gradle version is lower than ${DoctorService.MIN_SUPPORTED_GRADLE_VERSION}.`);
 			this.$logger.out("You will not be able to build your projects for Android or run them in the emulator or on a connected device." + EOL
 				+ `To be able to build for Android and run apps in the emulator or on a connected device, verify that you have at least ${DoctorService.MIN_SUPPORTED_GRADLE_VERSION} version installed.`);
@@ -106,5 +106,14 @@ class DoctorService implements IDoctorService {
 			this.$logger.out("TIP: To avoid setting up the necessary environment variables, you can use the Homebrew package manager to install the Android SDK and its dependencies." + EOL);
 		}
 	}
+
+	private isGradleVersionSupported(gradleVersion: string): boolean {
+		let minSupportedVersion = DoctorService.MIN_SUPPORTED_GRADLE_VERSION;
+		let requiredLength = _.max([gradleVersion.split(".").length, minSupportedVersion.split(".").length]);
+		gradleVersion = helpers.appendZeroesToVersion(gradleVersion, requiredLength);
+		minSupportedVersion = helpers.appendZeroesToVersion(minSupportedVersion, requiredLength);
+
+		return helpers.versionCompare(gradleVersion, minSupportedVersion) !== -1;
+	}
 }
 $injector.register("doctorService", DoctorService);