Void-safe library ECF files.
Fix GCC linker options order

GCC 4.6 has become fussier about the order of its options.
The -l options must now appear after the object files.

Without this patch, I have a GGC error when compiling a
custom project with gec:

 epm1.o: In function `T163f16':
 epm1.c:(.text+0xa9f): undefined reference to `pow'
 epm1.c:(.text+0xad4): undefined reference to `pow'

Tested on Ubuntu 12.04 LTS with GCC 4.6.3.

Links :
* http://nick.zoic.org/art/etc/gcc-linker-libs.html
* http://ubuntuforums.org/showthread.php?p=11339484
Synchronized with FreeELKS svn#711, except for the string and file classes.
Merge pull request #5 from oligot/gcc-link

Fix GCC linker options order
Fix GCC linker options order.
Merge pull request #4 from schoelle/master

Just some cleanup of the argument documentation
Made the code compile with the forthcoming ISE 7.2.
It still compiles with 7.0 and 7.1.
Accepts character literals of the form '%/0xNNNN/'.
This is needed to parse classes from EiffelBase 7.2.
Validity rules still need to be implemented.
Fixed bug in processing code in void-safe mode where the end of one of the branches of if-instructions or inspect-instructions is not reachable.
The computing of the list of initialized entities at the end of the instructions was erroneous.
Made sure that $GOBO_EIFFEL is correctly initialized when running gec and gelint.
Fixed bug when checking the signature of built-in features in void-safe mode.
The detachable type mark was not taken into account.
Fixed assertion violations.
Use void-safe version of FreeELKS. Adapted the compiler and runtime accordingly.
Based on FreeELKS svn#754.
Documentation explaining how to implement new built-in features in the Gobo Eiffel compiler.
* Fixed bug in features `force_last_new' and `put_last_new' of DS_HASH_TABLE.
* Fixed bug in DS_HASH_TABLE when the calls to `key_equality_tester' in
 `search_position' trigger the invariant which internally calls `search_position'.
  But this routine was not written to be re-entrant.
Improved implementation of class INTERNAL.
Fixed gec code generation for manifest CHARACTER_32 constants.
Made sure that TYPE.new_instance and TYPE.new_special_any_instance do not create objects of types which have not been marked as alive (which means that no object of that type is otherwise created in the system).
Removed feature `internal_meaning' in class EXCEPTION.
Made it interoperatable with FreeELKS void-safe mode.