Use Docker client for driver instead of exec (cnabio#185)

* Initial Docker client for driver

* Update to use HOME dir, docker attach

* Lint fix

* Update contaienr attach handling

* Added docker socket

* Updated to use Docker's CopyToContainer

* Lint fixes

* Hardcoded isTerm to false, refactored tar build

* Updated docker client creation

* Removed commented import

* Formatting fix

Co-authored-by: Jeremy Rickard <[email protected]>

driver.go

@@ -4,7 +4,6 @@ import (
 	"encoding/json"
 	"fmt"
 	"io"
-	"strings"
 )
 
 // ImageType constants provide some of the image types supported
@@ -106,7 +105,3 @@ func (d *DebugDriver) Config() map[string]string {
 func (d *DebugDriver) SetConfig(settings map[string]string) {
 	d.config = settings
 }
-
-func isTrue(val string) bool {
-	return strings.ToLower(val) == "true"
-}