Use in tests the generic method to pass config options

Instead of having variables being flipped around, just specify which Nginx
directives are needed in the configuration file.

t/03-exact_size_off.test

@@ -2,8 +2,7 @@
 cat <<---
 We test if the output from using "fancyindex_exact_size off" looks sane
 --
-EXACT_SIZE="off"
-nginx_start
+nginx_start 'fancyindex_exact_size off;'
 content=$(fetch)
 grep -e '[1-9]\.[0-9] KiB'  <<< "${content}"
 grep -E '[0-9]+ B'  <<< "${content}"

t/preamble

@@ -6,9 +6,6 @@
 # Distributed under terms of the MIT license.
 #
 
-# Configuration defaults
-EXACT_SIZE="on"
-
 function nginx_conf_generate () {
 	if ${DYNAMIC} ; then
 		echo 'load_module modules/ngx_http_fancyindex_module.so;'
@@ -30,7 +27,6 @@ function nginx_conf_generate () {
 			location / {
 				index index.html;
 				fancyindex on;
-				fancyindex_exact_size ${EXACT_SIZE};
 				$*
 			}
 		}