ola: fix compilation of this package

This package does not currently compile.

This is needed to do so that it compiles:
- fix emptying CXX variable in configure script
- fix automake not generating Makefile (remove doxygen definitions)
- force gnu++11 by patch, does not work with configure variable
Also because of changed API in libmicrohttpd:
- fix HttpServer

Moreover this package does not support --disable-slp configure option
anymore, remove it.

Signed-off-by: Marek Behún <kabel@blackhole.sk>

net/ola/patches/200-configure-acx-pthread.patch

@@ -0,0 +1,12 @@
+--- a/configure.ac
++++ b/configure.ac
+@@ -400,8 +400,7 @@ ACX_PTHREAD([
+              LIBS="$PTHREAD_LIBS $LIBS"
+              CFLAGS="$CFLAGS $PTHREAD_CFLAGS"
+              CXXFLAGS="$CXXFLAGS $PTHREAD_CXXFLAGS"
+-             CC="$PTHREAD_CC"
+-             CXX="$PTHREAD_CXX"],
++             CC="$PTHREAD_CC"],
+             [AC_MSG_ERROR([Missing pthread, please install it])])
+ 
+ # pthread_setname_np can take either 1 or 2 arguments.