Sort versions properly

From this:
```
$ m
    1.8.5
    2.0.7
    2.0.9
    2.2.1
    2.2.3
    2.2.4
    2.2.5
    2.2.6
    2.2.7
    2.4.1
    2.4.10
    2.4.11
    2.4.12
    2.4.3
    2.4.4
    2.4.5
    2.4.6
    2.4.7
    2.4.8
    2.4.9
    2.6.0
    2.6.1
    2.6.2
    2.6.3
    2.6.4
    2.6.5
    2.7.8
  ο 2.8.0-rc0
```
to this:
```
$ m
    1.8.5
    2.0.7
    2.0.9
    2.2.1
    2.2.3
    2.2.4
    2.2.5
    2.2.6
    2.2.7
    2.4.1
    2.4.3
    2.4.4
    2.4.5
    2.4.6
    2.4.7
    2.4.8
    2.4.9
    2.4.10
    2.4.11
    2.4.12
    2.6.0
    2.6.1
    2.6.2
    2.6.3
    2.6.4
    2.6.5
    2.7.8
  ο 2.8.0-rc0
```
Merge pull request #16 from gianpaj/patch-1

Sort versions properly