* ENHANCEMENT: install command

NOTE: this builds upon some of the previous pull requests I sent

https://github.com/subuser-security/subuser/issues/61

*as per:https://github.com/subuser-security/subuser/pull/84#issuecomment-35587683
moved common code to subuserlib

* some code cleanup: 
  * using python string.format
  * removing unused imports
  * make use of out new function: getAvailableProgramsText
  * renamed some variables: not good idea to call them the same as existing function names or imports
  * use some 'os.path.join' for path instead of simply +
  UnboundLocalError: local variable 'permissions' referenced before assignment
  * add argument to function: installExecutable(programName):
* added: paths.getMakeBaseImageScriptPath to have it in a cleaner way
  * replacing occurances with new function

* ENHANCEMENT: let multiple programs be installed from commandline



* installing a program there is much console output: there is too much output: a user will hardly recognize the nice info provided: add some space

```
update-alternatives: using /usr/bin/vim.basic to provide /usr/bin/vimdiff (vimdi
update-alternatives: using /usr/bin/vim.basic to provide /usr/bin/rvim (rvim) in auto mode.
update-alternatives: using /usr/bin/vim.basic to provide /usr/bin/rview (rview) in auto mode.
update-alternatives: using /usr/bin/vim.basic to provide /usr/bin/vi (vi) in auto mode.
update-alternatives: using /usr/bin/vim.basic to provide /usr/bin/view (view) in auto mode.
update-alternatives: using /usr/bin/vim.basic to provide /usr/bin/ex (ex) in auto mode.
update-alternatives: using /usr/bin/vim.basic to provide /usr/bin/editor (editor
Processing triggers for libc-bin ...
ldconfig deferred processing now taking place
 ---> aac3ac1199e9
Successfully built aac3ac1199e9
Removing intermediate container 9ca3bbceef36
Removing intermediate container c89f5638665d

============= INSTALLATION OK =============

vim: has been installed with the following permissions.
vim:
 Description: A simple powerful text editor
 Maintainer: Timothy Hobbs <timothyhobbs (at) seznam dot cz>
 Executable: /usr/bin/vim
 Can access the directory from which it was launched.
You can change this program's permissions at any time by editing it's permissions.json file.
workerm@notebook:~$ 
```