Tests: add TEST_GLOBALS and TEST_GLOBALS_HTTP config chunks. TEST_GLOBALS replaces previously used -g switch. This allows tests to be executed on 0.6.* branch. For compatibility with old tests -g switch will be used if TEST_GLOBALS wasn't expaneded in config. TEST_GLOBALS_HTTP replaces multiple variables (access_log, root, client_body_temp_path, proxy_temp_path, fastcgi_temp_path) previously specified directly in test configs. This change reduce duplication and allows tests to be used with nginx compiled without fastcgi and/or proxy modules (as proxy_temp_path and fastcgi_temp_path are added conditionally).

--- a/imap.t
+++ b/imap.t
@@ -33,6 +33,8 @@ my $t = Test::Nginx->new()
 	->run_daemon(\&Test::Nginx::IMAP::imap_test_daemon)
 	->write_file_expand('nginx.conf', <<'EOF')->run();
 
+%%TEST_GLOBALS%%
+
 master_process off;
 daemon         off;
 
@@ -50,11 +52,7 @@ mail {
 }
 
 http {
-    access_log    off;
-
-    client_body_temp_path  %%TESTDIR%%/client_body_temp;
-    fastcgi_temp_path      %%TESTDIR%%/fastcgi_temp;
-    proxy_temp_path        %%TESTDIR%%/proxy_temp;
+    %%TEST_GLOBALS_HTTP%%
 
     server {
         listen       127.0.0.1:8080;