GKE Cannot get a list of clusters/containers/pods

## Summary

Cannot get a list of GKE (Google Kubernetes Engine) clusters/containers or pods

## Detailed Information

As mentioned in the documentation, followed the get_driver API to get the container driver for the GKE provider. But got the below stacktrace.
```
Traceback (most recent call last):
File "/home/lkp//list-instances.py", line 146, in
main(sys.argv[1:])
File "/home/lkp/list-instances.py", line 51, in main
list_container_gce()
File "/home/lkp/list-instances.py", line 37, in list_container_gce
for cluster in driver.list_containers():
File "/usr/lib/python2.7/site-packages/libcloud/container/drivers/kubernetes.py", line 163, in list_containers
ROOT_URL + "v1/pods").object
File "/usr/lib/python2.7/site-packages/libcloud/container/drivers/gke.py", line 68, in request
response = super(GKEConnection, self).request(*args, **kwargs)
File "/usr/lib/python2.7/site-packages/libcloud/common/google.py", line 815, in request
*args, **kwargs)
File "/usr/lib/python2.7/site-packages/libcloud/common/base.py", line 650, in request
response = responseCls(**kwargs)
File "/usr/lib/python2.7/site-packages/libcloud/common/base.py", line 162, in __init__
self.object = self.parse_body()
File "/usr/lib/python2.7/site-packages/libcloud/common/google.py", line 278, in parse_body
raise ResourceNotFoundError(message, self.status, code)
libcloud.common.google.ResourceNotFoundError: u'\n\n \n \n Error 404 (Not Found)!!1\n \n *{margin:0;padding:0}html,code{font:15px/22px arial,sans-serif}html{background:#fff;color:#222;padding:15px}body{margin:7% auto 0;max-width:390px;min-height:180px;padding:30px 0 15px}* > body{background:url(//www.google.com/images/errors/robot.png) 100% 5px no-repeat;padding-right:205px}p{margin:11px 0 22px;overflow:hidden}ins{color:#777;text-decoration:none}a img{border:0}@media screen and (max-width:772px){body{background:none;margin-top:0;max-width:none;padding-right:0}}#logo{background:url(//www.google.com/images/branding/googlelogo/1x/googlelogo_color_150x54dp.png) no-repeat;margin-left:-5px}@media only screen and (min-resolution:192dpi){#logo{background:url(//www.google.com/images/branding/googlelogo/2x/googlelogo_color_150x54dp.png) no-repeat 0% 0%/100% 100%;-moz-border-image:url(//www.google.com/images/branding/googlelogo/2x/googlelogo_color_150x54dp.png) 0}}@media only screen and (-webkit-min-device-pixel-ratio:2){#logo{background:url(//www.google.com/images/branding/googlelogo/2x/googlelogo_color_150x54dp.png) no-repeat;-webkit-background-size:100% 100%}}#logo{display:inline-block;height:54px;width:150px}\n \n \n

404. That\u2019s an error.\n

The requested URL /v1/projects/absolute-point-196613/api/v1/pods was not found on this server. That\u2019s all we know.'

```
Libcloud version: 2.8.0, 3.0.0-rc1
Python version: 2.7, 3.7
OS: Fedora 30

libcloud/container/drivers/kubernetes.py:list_containers と libcloud/container/drivers/gke.py:request を読み、次に libcloud/common/google.py を通るリクエストを追跡してください。報告された 404 を再現し、なぜ /v1/projects/absolute-point-196613/api/v1/pods がリクエストされるのかを調査してください。GKE のクラスタ、コンテナ、Pod の一覧取得がこのレスポンスで失敗しなくなれば完了です。

索引モデルが issue の本文から書いたものです。