 5d50ad3941
			
		
	
	5d50ad3941
	
	
	
		
			
			* add trim function to `Spec` and `--ignore` option to 'spack diff' Allows user to compare two specs while ignoring the sub-DAG of a particular dependency, e.g. spack diff --ignore=mpi --ignore=zlib trilinos/abcdef trilinos/fedcba to focus on differences closer to the root of the software stack