Add option --[no-]bootstrap to server create

Create server without bootstraping when passed --no-bootstrap option.

ついでにこちらのフォークから修正を取り込み。 https://github.com/Amakata/knife-sakura/commit/b50fd96565c772bac1a586684ab695f8494cfb96

```
$ bundle exec knife sakura server create  --server-plan 1001 --disk-plan 4 --source-archive 112500463685 -n my_test --no-bootstrap 
[fog][WARNING] Create Server
[fog][WARNING] Create Volume
[fog][WARNING] Waiting disk until available
.[fog][WARNING] Modifing disk
Instance ID: 1126006xxxxx
Server Plan: プラン/1Core-1GB
Public IP Address: 133.242.xxx.xxx

## 作って一旦おしまい
$
```