nginx-util: add tests, clean up and fix issues

Add tests for nginx-ssl-util and nginx-ssl-util-nopcre using (fake)chroot.
Clean the code up making nginx-ssl-util a header file.
Both changes are for better (future) code quality only.

There are minor functional improvements:
* fix compiler error of gcc7 by using std=c++17
* fix error if there is no lan/loopback interface
* notice instead of error message if there is no default server
* add ipv6-prefix-assignment.*.local-address.address for LAN
* add CONFLICTS in Makefile for choosing the right version
* add cast to release of unique_ptr to avoid warning
* add version message to help message

Signed-off-by: Peter Stadler <peter.stadler@student.uibk.ac.at>

net/nginx-util/Makefile

@@ -1,13 +1,17 @@
 include $(TOPDIR)/rules.mk
 
 PKG_NAME:=nginx-util
-PKG_VERSION:=1.2
+PKG_VERSION:=1.3
 PKG_RELEASE:=1
+PKG_MAINTAINER:=Peter Stadler <peter.stadler@student.uibk.ac.at>
 
 include $(INCLUDE_DIR)/package.mk
 include $(INCLUDE_DIR)/cmake.mk
 
-define Package/nginx-util
+CMAKE_OPTIONS+= -DUBUS=y
+CMAKE_OPTIONS+= -DVERSION=$(PKG_VERSION)
+
+define Package/nginx-util/default
   SECTION:=net
   CATEGORY:=Network
   SUBMENU:=Web Servers/Proxies
@@ -15,23 +19,29 @@ define Package/nginx-util
   DEPENDS:=+libstdcpp +libubus +libubox +libpthread
 endef
 
+define Package/nginx-util
+  $(Package/nginx-util/default)
+  CONFLICTS:=nginx-ssl-util
+endef
+
 define Package/nginx-ssl-util/default
-  $(Package/nginx-util)
+  $(Package/nginx-util/default)
   TITLE+= and manager of its SSL certificates
   DEPENDS+= +libopenssl
   CONFLICTS:=nginx-util
-  PROVIDES:=nginx-ssl-util
 endef
 
 define Package/nginx-ssl-util
   $(Package/nginx-ssl-util/default)
   TITLE+= (using PCRE)
   DEPENDS+= +libpcre
+  CONFLICTS+= nginx-ssl-util-nopcre
 endef
 
 define Package/nginx-ssl-util-nopcre
   $(Package/nginx-ssl-util/default)
   TITLE+= (using <regex>)
+  CONFLICTS+= nginx-ssl-util
 endef
 
 define Package/nginx-util/description