move BuildUtils to WPUtils subtree, rename BuildUtils to PackageUtils and add getPackageInfo and getVersionCode methods
fix #1713: add package version code to mixpanel properties
use getVersionName in WordPress.java
remove unused method from ProfilingUtils
remove ProfilingUtils.getVersionName calls
move mContext assignement to the top of onCreate
Merge pull request #1764 from wordpress-mobile/issue/1713-send-version-code-to-mixpanel

fix #1713 send version code to mixpanel