Start work on Container and Process model

Signed-off-by: Michael Crosby <crosbymichael@gmail.com>

process.go

@@ -1,58 +0,0 @@
-package containerd
-
-import (
-	"errors"
-	"io"
-	"os"
-
-	specs "github.com/opencontainers/runtime-spec/specs-go"
-)
-
-var ErrNotExecProcess = errors.New("process not an exec process")
-
-type ProcessDelegate interface {
-	Pid() int
-	Wait() (uint32, error)
-	Signal(os.Signal) error
-}
-
-type Process struct {
-	Stdin  io.Reader
-	Stdout io.Writer
-	Stderr io.Writer
-
-	exec bool
-	s    *specs.Process
-
-	driver Runtime
-	c      *Container
-	d      ProcessDelegate
-}
-
-func (p *Process) Spec() *specs.Process {
-	return p.s
-}
-
-func (p *Process) Start() error {
-	if !p.exec {
-		return ErrNotExecProcess
-	}
-	d, err := p.driver.Exec(p.c, p)
-	if err != nil {
-		return err
-	}
-	p.d = d
-	return nil
-}
-
-func (p *Process) Pid() int {
-	return p.d.Pid()
-}
-
-func (p *Process) Wait() (uint32, error) {
-	return p.d.Wait()
-}
-
-func (p *Process) Signal(s os.Signal) error {
-	return p.d.Signal(s)
-}