listfiles download if necessary

listfiles was only working on packages that were already installed. You should
be able to list a packages files even if it is not installed, especially if it
has already been downloaded.

The function will now download the package if necessary, without installing, in
order to view the package files.

Other small changes

- conditional echo instead of piping to "head" in certain loops
- download function was exiting upon failure, when really it should just skip to
  next package
- simplified a grep statement

apt-cyg

@@ -148,24 +148,25 @@ apt-list () {
 
 apt-listfiles () {
   checkpackages
+  findworkspace
+  local pkg
   for pkg in $packages
   do
-    if [ -e /etc/setup/"$pkg".lst.gz ]
+    (( notfirst++ )) && echo
+    if [ ! -e /etc/setup/"$pkg".lst.gz ]
     then
-      gzip -cd /etc/setup/"$pkg".lst.gz
-    else
-      echo package $pkg is not installed
+      download "$pkg" || continue
     fi
-    echo
-  done |
-  head -c-1
+    gzip -cd /etc/setup/"$pkg".lst.gz
+  done
 }
 
 apt-show () {
   findworkspace
   checkpackages
   for pkg in $packages
   do
+    (( notfirst++ )) && echo
     awk '
     $1 == query {
       print
@@ -174,11 +175,9 @@ apt-show () {
     END {
       if (! fd)
         print "Unable to locate package " query
-      printf "\n"
     }
     ' RS='\n\n@ ' FS='\n' query="$pkg" setup.ini
-  done |
-  head -c-1
+  done
 }
 
 apt-depends () {
@@ -234,9 +233,9 @@ download () {
   awk '$1 == pc' RS='\n\n@ ' FS='\n' pc=$pkg setup.ini > release/$pkg/desc
   if [ ! -s release/$pkg/desc ]
   then
-    echo Package $pkg not found or ambiguous name, exiting
+    echo Package $pkg not found or ambiguous name
     rm -r release/"$pkg"
-    exit 1
+    return 1
   fi
   echo Found package $pkg >&2
 
@@ -263,6 +262,7 @@ download () {
     exit 1
   fi
 
+  tar tf $file | gzip > /etc/setup/"$pkg".lst.gz
   echo $file
 }
 
@@ -274,8 +274,7 @@ apt-search () {
     [[ $key ]] || key=$pkg
     for manifest in /etc/setup/*.lst.gz
     do
-      found=$(gzip -cd $manifest | grep -c "$key")
-      if (( found ))
+      if gzip -cd $manifest | grep -q "$key"
       then
         package=$(sed '
         s,/etc/setup/,,
@@ -320,12 +319,11 @@ apt-install () {
   echo
   echo Installing $pkg
 
-  file=$(download $pkg)
+  file=$(download $pkg) || continue
   cd release/$pkg
   echo Unpacking...
-  tar xvf $file -C / > /etc/setup/"$pkg".lst
-  gzip -f /etc/setup/"$pkg".lst
 
+  tar -x -C / -f $file
   # update the package database
 
   awk '