rocket auto-alignment: should detect trailing ; as a boundary to stop alignment

[lelutin]

In the case where multiple resources are defined in the same block with a ; to end the definition of one resource, the current auto-alignment will continue going up or down until it encounters a curly brace. this means that all of the different resources will be aligned at the same level, which is usually not useful.

For example in the following snippet with the cursor placed at the right of the final content:

file {  
  'blah': content => 'bloh';
  'moo': content => 'meuh';
  'verylongfilename': content 
}

typing => there will produce this:

file {  
  'blah': content             => 'bloh';
  'moo': content              => 'meuh';                                                                        
  'verylongfilename': content => 
}

whereas the following would rather be expected:

file {  
  'blah': content => 'bloh';
  'moo': content => 'meuh';
  'verylongfilename': content => 
}

the part of the auto-alignment function that discovers lines above and below the current one should also check for a trailing ; (with possible spaces and comment at its right) and stop the discovery at that point. when going up, stop without the line containing the ;, but when going down, include the line that contains the ; in the zone that needs alignment.

[lelutin]

blocking only on a trailing ; for lines below the cursor is not great since there can also be a new resource with a hash of params instead.

there's also another issue with alignments for multiple resources within the same block if we instead use gq to format:

 file {                                                                                            
   a:                                                                                              
     mode => '0700',                                                                        
     content => 'aaaaa';                                                                           
   b: owner  => 'zzz';                                                                             
   see: mode   => '1754';                                                                          
 }

with the cursor on any line inside the file block, running gq} will align all hashrockets across different resources, which is not what we want. we'd want only the params for a to have their hashrockets aligned to one another and b and see should be left as-is just without the extra spaces between the param name and the hashrocket.