fetch_bits will not re-download if directory exists

Signed-off-by: dmitriy kalinin <dmitriy@pivotallabs.com>
fetch_bits separately from symlinking installed bits

Signed-off-by: dmitriy kalinin <dmitriy@pivotallabs.com>
removed unused methods

Signed-off-by: dmitriy kalinin <dmitriy@pivotallabs.com>
aw agent prepare msg response

Signed-off-by: dmitriy kalinin <dmitriy@pivotallabs.com>
Prefer single quotes for uninterpolated strings

Signed-off-by: Jesse Zhang <jz@pivotallabs.com>
Clean up agent_client_spec

Signed-off-by: Jesse Zhang <jz@pivotallabs.com>
Add spec that long-running messages have polling

Signed-off-by: Jesse Zhang <jz@pivotallabs.com>
Introduce instance preparer

Prepares an agent prior to apply if it is not detached

Signed-off-by: Jesse Zhang <jz@pivotallabs.com>