__package_apt: add --install-recommends parameter

For a good reason, __package_apt doesn't install recommended packages as
default. But the option --install-recommends comes handy if you want to
install a package where you want to install all recommended packages
(and not to install all of them separately).

Also, the manpage now explains that the type won't install recommended
packages by default.

cdist/conf/type/__package_apt/gencode-remote

@@ -42,6 +42,13 @@ else
    target_release=""
 fi
 
+if [ -f "$__object/parameter/install-recommends" ]; then
+    # required if __apt_norecommends is used
+    recommendsparam="-o APT::Install-Recommends=1"
+else
+    recommendsparam="-o APT::Install-Recommends=0"
+fi
+
 if [ -f "$__object/parameter/purge-if-absent" ]; then
 	purgeparam="--purge"
 else
@@ -62,16 +69,16 @@ case "$state_is" in
     ;;
 esac
 
-# Hint if we need to avoid questions at some point:
-# DEBIAN_PRIORITY=critical can reduce the number of questions
-aptget="DEBIAN_FRONTEND=noninteractive apt-get --quiet --yes -o APT::Install-Recommends=0 -o Dpkg::Options::=\"--force-confdef\" -o Dpkg::Options::=\"--force-confold\""
-
 if [ "$state_is" = "$state_should" ]; then
     if [ -z "$version" ] || [ "$version" = "$version_is" ]; then
         exit 0;
     fi
 fi
 
+# Hint if we need to avoid questions at some point:
+# DEBIAN_PRIORITY=critical can reduce the number of questions
+aptget="DEBIAN_FRONTEND=noninteractive apt-get --quiet --yes -o Dpkg::Options::=\"--force-confdef\" -o Dpkg::Options::=\"--force-confold\""
+
 case "$state_should" in
     present)
         # following is bit ugly, but important hack.
@@ -85,7 +92,7 @@ EOF
         if [ -n "$version" ]; then
             name="${name}=${version}"
         fi
-        echo "$aptget install $target_release '$name'"
+        echo "$aptget $recommendsparam install $target_release '$name'"
         echo "installed" >> "$__messages_out"
     ;;
     absent)

cdist/conf/type/__package_apt/man.rst

@@ -9,7 +9,9 @@ cdist-type__package_apt - Manage packages with apt-get
 DESCRIPTION
 -----------
 apt-get is usually used on Debian and variants (like Ubuntu) to
-manage packages.
+manage packages. The package will be installed without recommended
+or suggested packages. If such packages are required, install them
+separatly or use the parameter ``--install-recommends``.
 
 This type will also update package index, if it is older
 than one day, to avoid missing package error messages.
@@ -39,6 +41,15 @@ version
 
 BOOLEAN PARAMETERS
 ------------------
+install-recommends
+    If the package will be installed, it also installs recommended packages
+    with it. It will not install recommended packages if the original package
+    is already installed.
+
+    In most cases, it is recommended to install recommended packages separatly
+    to control which additional packages will be installed to avoid useless
+    installed packages.
+
 purge-if-absent
     If this parameter is given when state is `absent`, the package is
     purged from the system (using `--purge`).

cdist/conf/type/__package_apt/parameter/boolean

@@ -1 +1,2 @@
+install-recommends
 purge-if-absent