Remove mustache dependency (#41)

Description
===========

While checking the reason for failing android plugin execution together
with the new release plugin I found that we still have this unused
dependency.

Changes
=======

![REMOVE] unused dependency `om.github.spullara.mustache.java:compiler`

build.gradle

@@ -51,7 +51,6 @@ dependencies {
 
     compile 'com.netflix.nebula:nebula-release-plugin:6.+'
     compile 'org.ajoberstar:gradle-git:1.7.+'
-    compile 'com.github.spullara.mustache.java:compiler:0.8.18'
     compile 'cz.malohlava:visteg:1.0.+'
     compile 'gradle.plugin.net.wooga.gradle:atlas-paket:1.+'
     compile 'gradle.plugin.net.wooga.gradle:atlas-github:1.+'