Initial files for Debian Package.

[sjha2048]

This Pull request is for creating the Debian package for arthas and this is all of my initial files.

for testing the package run

mvn clean install

this will create arthas.deb inside /packaging/target directory which can be installed by dpkg.

[CLAassistant]

All committers have signed the CLA.

[hengyunabc]

Add dir format in packaging/src/main/assembly/assembly.xml, then the deb plugin can package files from the directory? No need to configure multiple items.

   <formats>
     <format>zip</format>
    <format>dir</format>
   </formats>

[sjha2048]

I tried this approach but I am facing several build errors in this method like file permission issues and target directory location, but instead of configuring multiple items I'll try to make a template type of package, will update you on this till tomorrow morning

[hengyunabc]

Need to update packaging/src/main/assembly/assembly.xml

   <formats>
+    <format>dir</format>
     <format>zip</format>
   </formats>

[sjha2048]

Will do it!

[hengyunabc]

travis-ci fixed.

[sjha2048]

thank you @hengyunabc