* now 2 files with stimuli data: data_input.txt & key_input.txt
* new file with the expetcted data output: data_output.txt
* new test: Inverse permutation known answer test

* now 2 seperate processes: key scheduling & data path
* keys are now concurrent wire assignments

* functions s1() - s8() returned incorrect slices of the matrix
* function s2() had one incorrect nibble in cause of faulty conversion

This reverts commit 4b41ea24dd.

This reverts commit 3ff9e3e269.

This reverts commit fdc730de69.

new generic in aes.vhd: ovl_enable (boolean); copy of aes_pkg.vhd to
integrate ovl functions; copy of tb_aes.vhd to integrate ovl function

move all rtl *.vhd files into the new vhdl directory in the rtl
directory

- OVL now in own library 'accellera_ovl_vhdl
- OVL now default setting
- definition of control OVL configuration record 'ovl_proj_controls' in
package file 'aes_pkg.vhd'

- new variable OVL_ENABLE to enable OVL compile
- new variables OVL_LOC & OVL_SRC which point to the OVL library files
- new GHDL analyze of the OVL library

- new variable OVL_ENABLE to enable OVL compile
- new variables OVL_LOC & OVL_SRC which point to the OVL library files
- new GHDL analyze of the OVL library