FIX hopefully the problem with spaces in tags

https://github.com/subuser-security/subuser/issues/99

I put a bit more of example usage in it: if you do not like just erase them: some examples

```
workerm@notebook:~$ subuser save-compressed-images docker
('getAllRepoNameWhichStartWith: ', ['subuser-firefox', 'subuser-firefox', 'subuser-libx11', 'subuser-vim'])


getUniqueRowByRepTag 'subuser-firefox', 'latest' : <{'SIZE': '402.1 MB', 'TAG': 'latest', 'ID': '197837e70eb5cc29dae51cfcc191263bbdbbaa8fd0b7a2088d7e2d1461944610', 'REPOSITORY': 'subuser-firefox', 'CREATED': '33 hours ago'}>

("Search for tags with spaces: 'zz  233  e', 'dgfz 45' ", {'SIZE': '204.4 MB', 'TAG': 'dgfz 45', 'ID': '9cd978db300e27386baa9dd791bf6dc818f13e52235b26e95703361ec3c94dc6', 'REPOSITORY': 'zz  233  e', 'CREATED': '2 weeks ago'})

SIZE: <402.1 MB>

FOUND: 'subuser-firefox', 'latest'

('getImageTagOfProgram: ', 'subuser-firefox')
workerm@notebook:~$ 

```
Update dockerImages.py

maybe better to default it to latest with our current code
added: getSubuserDockerRepoNameTagsText

this is similar to: 
*getAvailableProgramsText(addNewLine=False, indentSpaces=0):
*getInstalledProgramsText(addNewLine=False, indentSpaces=0):

but does it for docker images themself 

e.g.
```
workerm@notebook:~$ subuser save-compressed-images docker
    subuser-firefox:Tag w ith 34
    subuser-firefox:latest
    subuser-libx11:latest
    subuser-vim:latest

workerm@notebook:~$ 
```

the funny one is where I tested spaced in tags
Merge branch 'patch-2' of https://github.com/peter1000/subuser

Conflicts:
	logic/subuserCommands/subuserlib/dockerImages.py