Mkr serializer

Re-implementation of mKR serializer using raptor_serialize_turtle.c and raptor_turtle_writer.c
context->emit_mkr = 1 for mkr, = 0 for turtle in raptor_serialize_turtle.c
Ditto for new emit_mkr argument for _prefix and _base procedures in raptor_turtle_writer.c
> In tests/mkr/Makefile.mkr:
> 
> > @@ -0,0 +1,76 @@
> > +# -*- Mode: Makefile -*-
> FYI The error is reproducible as follows: ./autogen.sh make ... cd scripts ... gcc ... -I/usr/include/libxml2 build-formats.c -o
> build-formats build-formats.c:29:21: fatal error: raptor2.h: No such file or directory #include <raptor2.h> ^ It fails because
> raptor2.h is in ../src not /usr/include/libxml2
> If I use --enable-maintainer-mode --disable-gtk-doc it succeeds. And then make check fails on turtle tests -- which I will fix. Dick

The normal build will find raptor2.h in the ../src - if it's not there, 
configure has not run. configure has to run to create raptor2.h,
raptor_config.h and Makefile amongst other files.

in the dir:

$ make build-formats V=1
gcc -DHAVE_CONFIG_H -I. -I../src   -Wall -Wc++-compat -Wextra -Wunused 
-Waggregate-return -Wbad-function-cast -Wcast-align 
-Wdeclaration-after-statement -Wdisabled-optimization -Wdiv-by-zero 
-Wendif-labels -Werror-implicit-function-declaration -Wfloat-equal 
-Wframe-larger-than=4096 -Winit-self -Winline -Wmissing-declarations 
-Wmissing-format-attribute -Wmissing-noreturn -Wmissing-prototypes 
-Wnested-externs -Wold-style-definition -Wpacked -Wpointer-arith 
-Wredundant-decls -Wshadow -Wsign-compare -Wstrict-prototypes 
-Wswitch-enum -Wundef -Wunreachable-code -Wunsafe-loop-optimizations 
-Wwrite-strings -Wno-conversion -Wno-format-nonliteral 
-Wno-missing-field-initializers -Wno-sign-conversion -Wno-system-headers 
-Wno-unused-parameter -DRAPTOR_INTERNAL=1 -I/usr/include/libxml2 
-I/usr/include/libxml2     -MT build-formats.o -MD -MP -MF 
.deps/build-formats.Tpo -c -o build-formats.o build-formats.c
mv -f .deps/build-formats.Tpo .deps/build-formats.Po
/bin/bash ../libtool  --tag=CC   --mode=link gcc     -o build-formats 
build-formats.o ../src/libraptor2.la
libtool: link: gcc -o .libs/build-formats build-formats.o 
../src/.libs/libraptor2.so

and if raptor2 is in ../src, it'll be found

Dave