Modify bundler task to fix deprecation warnings

[jp524]

Resolves #714.

While configuring mina on my project I noticed deprecation warnings for bundle flags. I modified the commands in the bundle:install task in my project and would like to offer the same changes here.

Refer to bundle config documentation for current release 2.5.

[Antronin]

Please merge this as the deprecation is really old and suddenly it will stop working.