removing old proguard config, adding a new that was generated by android project for #9
for #9 another potential loss of javascript interface functions can come when methods are obfiscated using proguard source https://groups.google.com/forum/?fromgroups=#!topic/android-developers/-InoRvv37D8 http://stackoverflow.com/questions/7424510/uncaught-typeerror-when-using-a-javascriptinterface
for #9 updating project properties ot a generated properties from android sdk17