Fix capitalization of command help summaries

Change-Id: Ibb245fdca5470efa6340af019b452dd17b01e9c2
Signed-off-by: David Pursehouse <david.pursehouse@gmail.com>

org.eclipse.jgit.pgm/resources/org/eclipse/jgit/pgm/internal/CLIText.properties

@@ -285,7 +285,7 @@ usage_actOnRemoteTrackingBranches=act on remote-tracking branches
 usage_addFileContentsToTheIndex=Add file contents to the index
 usage_alterTheDetailShown=alter the detail shown
 usage_approveDestructionOfRepository=approve destruction of repository
-usage_archive=zip up files from the named tree
+usage_archive=Zip up files from the named tree
 usage_archiveFormat=archive format. Currently supported formats: 'tar', 'zip', 'tgz', 'tbz2', 'txz'
 usage_archiveOutput=output file to write the archive to
 usage_archivePrefix=string to prepend to each pathname in the archive
@@ -384,7 +384,7 @@ usage_resetMixed=Resets the index but not the working tree
 usage_runLfsStore=Run LFS Store in a given directory
 usage_S3NoSslVerify=Skip verification of Amazon server certificate and hostname
 usage_setTheGitRepositoryToOperateOn=set the git repository to operate on
-usage_show=display one commit
+usage_show=Display one commit
 usage_showRefNamesMatchingCommits=Show ref names matching commits
 usage_showPatch=display patch
 usage_showNotes=Add this ref to the list of note branches from which notes are displayed