[master] 1941f86 Append a default system-wide location to vmod_path

[Dridi Boukelmoune]

commit 1941f8638814e30d879af6eb2e9e129c503512f1
Author: Dridi Boukelmoune <dridi.boukelmoune at gmail.com>
Date:   Thu Aug 25 23:02:01 2016 +0200

    Append a default system-wide location to vmod_path
    
    By default: /usr/share/vcl
    
    This directory becomes a drop-in, and standard location for library-like
    VCL files. It streamlines third-party VCL packaging, offering a blessed
    for installation, leaving the canonical /etc/varnish directory entirely
    to the end-user.
    
    While it is common to see VMOD packages in the wild, there are some VCL
    libraries (sometimes backed by VMODs) that would benefit some form of
    standardization. It then becomes possible to install packages, and use
    relative includes that JustWork(tm). This is especially true for VCL
    libraries that are split into several files, they can put themselves in
    a subdirectory in /usr/share/vcl and use it as a namespace for includes
    between files of the library:
    
        # somewhere in my awesome "foo" library
        include "foo/some_feature.vcl"
    
    Choosing a default path of `/etc/varnish:/usr/share/vcl` prevents VCLs
    dropped in the system from shadowing end-users VCLs but at the same
    empowers said users to override a "standard" VCL in their `/etc` tree,
    with no additional parameters fiddling.

diff --git a/bin/varnishd/Makefile.am b/bin/varnishd/Makefile.am
index 892b9c6..d629a4a 100644
--- a/bin/varnishd/Makefile.am
+++ b/bin/varnishd/Makefile.am
@@ -145,7 +145,7 @@ varnishd_CFLAGS = \
 	-DVARNISHD_IS_NOT_A_VMOD \
 	-DVARNISH_STATE_DIR='"${VARNISH_STATE_DIR}"' \
 	-DVARNISH_VMOD_DIR='"${pkglibdir}/vmods"' \
-	-DVARNISH_VCL_DIR='"${varnishconfdir}"'
+	-DVARNISH_VCL_DIR='"${varnishconfdir}:${datarootdir}/varnish/vcl"'
 
 varnishd_LDFLAGS = -export-dynamic