Pass a :keys option to Net::SSH

For the --private-key option to work, we need to consistently
use the :keys option when accessing remote servers.
Make SSH keys set with --private-key work in 'bosh-bootstrap ssh'

The code to do this was already present, but commented out.  The
only reason it didn't work is because "-i #{private_key_path}" makes
ssh attempt to use the key path with a prepended space char.
Merge pull request #131 from dpw/fix-private-key

--private-key fixes
fix specs
bump to 0.7.1
Use bundle binstubs instead of broken rake all:install [fixes #137]
Merge pull request #138 from rkoster/broken-edge-deployer

Use bundle binstubs instead of broken rake all:install [fixes #137]
Test that ICMP ports can be opened
Create new security group ""#{bosh_name}-inception-vm" and assign it to inception-vm
Open ICMP "port" 7 (echo reply) for inception-vm sg
Update test security group expectations
add gemfury gem version badge
clean up spec to use $HOME set for all specs
Create a keypair for the inception VM and store locally [closes #42]
Using local private key for fog to setup VM
Using inception VM private key for remote server command
Remove --private-key options as inception key is generated now
inception private key stored in ~/.bosh_bootstrap/ssh or $SETTINGS/ssh folder
update changelog for new inception key feature
WIP to migrate old inception key settings to new format