Renamed directory lang/ into clang/

The directory clang/ contains modules for scanning,parsing,
and translating computer languages (compiler support modules).
The transC implementation technique was a meander.

A future implementation will use a Packrat parser,
a compiler generatorr like ANTLR or something else.
Move utf8scanner from clang/ into io/reader/
Remove warnings generated by -Wstrict-overflow=5

The Release mode switches on optimization level -O2
which in turn switches on
 -fstrict-overflow:
   (excerpt from man gcc)
   Allow the compiler to assume strict signed overflow rules,
   depending on the language being compiled.  For C (and C++) this
   means that overflow when doing arithmetic with signed numbers is
   undefined, which means that the compiler may assume that it will
   not happen.

Added warning "-Wstrict-overflow=5" to projekte/binary.gcc and
projekte/shared.gcc which warns about optimizations done
cause -fstrict-overflow is active.

Changed source code to remove all newly generated warnings.

Signed overflow is undefined behaviour in the C language.
To switch off any optimization with strict-overflow
you can use -fno-strict-overflow. But on a machine which
has non twos-complement negative numbers the behaviour
differs. So -fwrapv exists which ensures a twos-complement
representation of negative values and therefore -fwrapv
makes signed overflow (gcc implementation) defined behaviour.
Add color to text output of run_statictest.sh
Rename initwaitconnect into initaccept

The name initaccept_ipsocket resembles the accept system call
and is therefore more easy to remember.

Turned SO_LINGER off for all sockets.
Implement sizeusable_malloc

The function returns the number of usable bytes of an allocated
memory block. The memory block must have been allocated with a call
to malloc(size). The returned value is >= size.