apr: bump to 1.7.0 & sync with master

This is a squash of the following cherry-picked commits:

40a29bf055
40c7e95210
893a804c95
12037b3f29
193c3913b6
430ab5f9b3
0c6d461cc9
86396c6a49

Short summary:

- version is bumped to 1.7.0
- Makefile and patches are updated and cleaned
- adds myself as maintainer
- improves the cross-compile setup (via configure variables, patches &
  sed scripts)

For more details please check the individual commits provided above.

Signed-off-by: Sebastian Kemper <sebastian_ml@gmx.net>

libs/apr/patches/001-cross-compile.patch

@@ -0,0 +1,56 @@
+Fix cross-compilation
+
+Patch was backported from Apache httpd:
+http://svn.apache.org/viewvc?view=revision&revision=1327907
+http://svn.apache.org/viewvc?view=revision&revision=1328390
+http://svn.apache.org/viewvc?view=revision&revision=1328714
+
+Patch submitted upstream:
+https://issues.apache.org/bugzilla/show_bug.cgi?id=57058
+
+Signed-off-by: Bernd Kuhls <bernd.kuhls@t-online.de>
+
+--- a/configure.in
++++ b/configure.in
+@@ -118,6 +118,16 @@ AC_CANONICAL_SYSTEM
+ echo "Configuring APR library"
+ echo "Platform: $host"
+ 
++dnl In case of cross compilation we set CC_FOR_BUILD to cc unless
++dnl we got already CC_FOR_BUILD from environment.
++if test "x${build_alias}" != "x${host_alias}"; then
++  if test "x${CC_FOR_BUILD}" = "x"; then
++    CC_FOR_BUILD=cc
++  fi
++fi
++AC_SUBST(CC_FOR_BUILD)
++AC_SUBST(CFLAGS_FOR_BUILD)
++
+ dnl Some initial steps for configuration.  We setup the default directory
+ dnl and which files are to be configured.
+ 
+--- a/Makefile.in
++++ b/Makefile.in
+@@ -8,6 +8,8 @@ top_blddir=@apr_builddir@
+ # APR (Apache Portable Runtime) library Makefile.
+ #
+ CPP = @CPP@
++CC_FOR_BUILD = @CC_FOR_BUILD@
++CFLAGS_FOR_BUILD = @CFLAGS_FOR_BUILD@
+ 
+ # get substituted into some targets
+ APR_MAJOR_VERSION=@APR_MAJOR_VERSION@
+@@ -136,8 +138,13 @@ tools/gen_test_char.lo: tools/gen_test_c
+ 	$(APR_MKDIR) tools
+ 	$(LT_COMPILE)
+ 
++ifdef CC_FOR_BUILD
++tools/gen_test_char@EXEEXT@: tools/gen_test_char.c $(LOCAL_LIBS)
++	$(CC_FOR_BUILD) $(CFLAGS_FOR_BUILD) -DCROSS_COMPILE -o $@ $<
++else
+ tools/gen_test_char@EXEEXT@: $(OBJECTS_gen_test_char)
+ 	$(LINK_PROG) $(OBJECTS_gen_test_char) $(ALL_LIBS)
++endif
+ 
+ include/private/apr_escape_test_char.h: tools/gen_test_char@EXEEXT@
+ 	$(APR_MKDIR) include/private