Default to Unbuntu 14.04 and clean up/simplify some options
Default to Unbuntu 14.04 and clean up/simplify some options

writecodedrinkcoffee/vagrant-lemtl,aaronstoddard/vagrant-lemtl,writecodedrinkcoffee/vagrant-lemtl,writecodedrinkcoffee/vagrant-lemtl,aaronstoddard/vagrant-lemtl,mikesprague/vagrant-lemtl,mikesprague/vagrant-lemtl,aaronstoddard/vagrant-lemtl