Shorter help strings.

lib/spack/spack/cmd/checksum.py

@@ -38,7 +38,7 @@
 from spack.stage import Stage, FailedDownloadError
 from spack.version import *
 
-description ="Checksum available versions of a package to update a package file."
+description ="Checksum available versions of a package."
 
 def setup_parser(subparser):
     subparser.add_argument(

lib/spack/spack/cmd/pkg.py

@@ -31,7 +31,7 @@
 import spack
 from spack.util.executable import *
 
-description = "Query packages associated with particular git revisions in spack."
+description = "Query packages associated with particular git revisions."
 
 def setup_parser(subparser):
     sp = subparser.add_subparsers(