Revamped alr version output

[mosteo]

Fixes #833
Fixes #607 (but for the alr --version flag, which I guess will be simpler to do with aliases)

Example of the new output:

$ alr version
APPLICATION                                                                                   
alr version:            1.1.0-rc3                                                             
libalire version:       1.1.0-rc3                                                             
compilation date:       2021-09-16 12:15:56                                                   
compiler version:       Community 2021 (20210519-103)                                         
                       
CONFIGURATION          
config folder:          /home/jano/.config/alire                                              
force flag:             FALSE                                                                 
non-interactive flag:   FALSE                                                                 
community index branch: devel-1.1                                                             
indexes folder:         /home/jano/.config/alire/indexes                                      
indexes metadata:       OK                                                                    
index #1:               (community) git+https://github.com/alire-project/alire-index#devel-1.1
toolchain assistant:    disabled                                                              
tool #1 gnat:           gnat_external=2021.0.0                                                
tool #2 gprbuild:       not configured                                                        
                       
WORKSPACE              
root status:            VALID                                                                 
root release:           alr=1.1.0-dev                                                         
root load error:        none                                                                  
root folder:            /home/jano/prog/alire                                                 
current folder:         /home/jano/prog/alire/testsuite                                       
                       
SYSTEM                 
distribution:           UBUNTU                                                                
os:                     LINUX                                                                 
target:                 NATIVE                                                                
toolchain:              USER                                                                  
word-size:              BITS_64