configure.ac: enable running tests in parallel

Closes #132

.gitignore

@@ -27,3 +27,4 @@ Makefile.in
 /stamp-h1
 /test/test.ACL
 /test/test.SELINUX
+/test-driver

.travis.yml

@@ -112,11 +112,11 @@ script:
   - ./autogen.sh
   - ./configure --enable-werror CC=$COMPILER
   - make
-  - make check
-  - make distcheck
+  - make -j9 check
+  - make -j9 distcheck
   # nodeps because rpm build deps can not be installed on debian system
   - make rpm RPM_FLAGS="--nodeps"
-  - sed 's|/bin/bash|/bin/dash|' -i test/*.sh && make check
+  - sed 's|/bin/bash|/bin/dash|' -i test/*.sh && make -j9 check
 notifications:
   email:

configure.ac

 AC_INIT([logrotate],m4_esyscmd([build-aux/git-version-gen --prefix '' .tarball-version]),
 [],[],[https://github.com/logrotate/logrotate])
-dnl serial-test not supported prior version 1.12
-m4_define([serial_tests], [
-    m4_esyscmd([automake --version |
-                perl -nae '{@v = split("[.]", $F[-1]);
-                            if ($v[0] >= 1 && $v[1] >= 12)
-                                {print "serial-tests\n";}
-                            exit;}'
-    ])
-])
-
 dnl foreign: Do not require AUTHORS, ChangeLog, NEWS, and README to exist
-dnl serial_tests: Do not hide standard output of our sequential test-suite
 dnl dist-xz: Produce tar.xz version of the release archive
-AM_INIT_AUTOMAKE(foreign dist-xz serial_tests)
+AM_INIT_AUTOMAKE(foreign dist-xz)
 # --enable-silent-rules
 m4_ifdef([AM_SILENT_RULES],