fixed multi sortOrder bug in LexalParser

Fixed bug when multiple sort orders have to be parsed. Bug reported in issue https://github.com/Indomitable/monodevelop-tfs-addin/issues/2

Example:

```SQL
    SELECT [System.Id], 
           [Microsoft.VSTS.Common.StackRank], 
           [Microsoft.VSTS.Common.Priority], 
           [System.State], 
           [Microsoft.VSTS.Scheduling.RemainingWork], 
           [Microsoft.VSTS.Scheduling.CompletedWork], 
           [System.Title] 
      FROM WorkItems 
     WHERE [System.TeamProject] = @project 
       AND [System.AssignedTo] = @me 
       AND [System.WorkItemType] = 'Aufgabe' 
       AND [System.State] <> 'Geschlossen' 
       AND [System.State] <> 'Entfernt' 
  ORDER BY [System.State], 
           [Microsoft.VSTS.Common.StackRank], 
           [Microsoft.VSTS.Common.Priority], 
           [System.Id]
```

Linefeed at the beginning splits order by statement into two elements.
![capturfiles_32](https://cloud.githubusercontent.com/assets/5220162/5354214/3850060e-7f85-11e4-9d83-6d81039e581d.jpg)