Created Usage of Intel's C/C++ compiler (markdown)

Usage-of-Intel's-C-C---compiler.md

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+If you are interested to use Intel's C/C++ compiler instead of the GCC, you have to guarantee with the compiler flag `-ffreestanding` that the compiler doesn't use the standard environment of your host system. Instead of using the standard path, you have to set with the compiler flag `-I` the include path to HermitCore's environment. However, Intel's compiler creates per default object files for the host system. Our toolchain includes the program `x86_64-hermit-elfedit` that is able to convert with the flag `--output-osabi HermitCore` these files to HermitCore's object files. For linking all object files to a HermitCore executable, you have to use the linker of our toolchain because it includes a valid linker script, which is required to build a bootable executable.
+
+To summarize this guideline, you find below an [abstract of a Makefile](https://github.com/RWTH-OS/HermitCore/blob/master/hermit/usr/benchmarks/Makefile), which creates a HermitCore executable for the [stream benchmark](https://github.com/RWTH-OS/HermitCore/blob/master/hermit/usr/benchmarks/stream.c). 
+
+    ELFEDIT_FOR_TARGET = x86_64-hermit-elfedit
+    CC_FOR_TARGET = x86_64-hermit-gcc
+    CC = icc
+    CFLAGS = -m64 -O3 -xHost -I$(TOPDIR)/hermit/usr/x86/x86_64-hermit/include/ -openmp -ffreestanding
+    STRIP_DEBUG = --strip-debug
+    KEEP_DEBUG = --only-keep-debug
+
+    default: stream
+
+    stream.o: stream.c
+        $(CC) -c $(CFLAGS) -o $@ $<
+        $(ELFEDIT_FOR_TARGET) --output-osabi HermitCore $@
+
+    stream: stream.o
+        $(CC_FOR_TARGET) -fopenmp -o $@ $<
+        $(OBJCOPY_FOR_TARGET) $(KEEP_DEBUG) $@ $@.sym
+        $(OBJCOPY_FOR_TARGET) $(STRIP_DEBUG) $@