Fix root location when repacking application

[lyrixx]

fixes #442

Explaination (see root directory)

Default behavior (without phar)

>/tmp/foobar/castor-phar-location(main *%) castor debug
 ---------------------- ------------------------------------------------------------- 
  Application name       castor                                                       
  Application version    v0.15.0                                                      
  Root directory         /tmp/foobar/castor-phar-location                             
  Cache directory        /home/gregoire/.cache/castor                                 
  Current context name                                                                
  Current context data   {                                                            
                             "name": "",                                              
                             "data": [],                                              
                             "environment": [],                                       
                             "workingDirectory": "/tmp/foobar/castor-phar-location",  
                             "tty": false,                                            
                             "pty": true,                                             
                             "timeout": null,                                         
                             "quiet": false,                                          
                             "allowFailure": false,                                   
                             "notify": null,                                          
                             "verbosityLevel": -1,                                    
                             "notificationTitle": ""                                  
                         }                                                            
 ---------------------- ------------------------------------------------------------- 

Without my patch, and with the phar

>/tmp/foobar/castor-phar-location(main *%) ./my-app.linux.phar  debug
 ---------------------- ---------------------------------------- 
  Application name       castor                                  
  Application version    v0.15.0                                 
  Root directory         /tmp/foobar                             
  Cache directory        /home/gregoire/.cache/castor            
  Current context name                                           
  Current context data   {                                       
                             "name": "",                         
                             "data": [],                         
                             "environment": [],                  
                             "workingDirectory": "/tmp/foobar",  
                             "tty": false,                       
                             "pty": true,                        
                             "timeout": null,                    
                             "quiet": false,                     
                             "allowFailure": false,              
                             "notify": false,                    
                             "verbosityLevel": -1                
                         }                                       
 ---------------------- ---------------------------------------- 

Why my patch, and with the phar

>/tmp/foobar/castor-phar-location(main *%) ./my-app.linux.phar  debug
 ---------------------- ------------------------------------------------------------- 
  Application name       castor                                                       
  Application version    v0.15.0                                                      
  Root directory         /tmp/foobar/castor-phar-location                             
  Cache directory        /home/gregoire/.cache/castor                                 
  Current context name                                                                
  Current context data   {                                                            
                             "name": "",                                              
                             "data": [],                                              
                             "environment": [],                                       
                             "workingDirectory": "/tmp/foobar/castor-phar-location",  
                             "tty": false,                                            
                             "pty": true,                                             
                             "timeout": null,                                         
                             "quiet": false,                                          
                             "allowFailure": false,                                   
                             "notify": false,                                         
                             "verbosityLevel": -1                                     
                         }                                                            
 ---------------------- ------------------------------------------------------------- 

[pyrech]

Thanks