eCos for Nios II 5.0 now available

This is essentially a bug fix release to track the new version of the Nios II kit. The headline changes are:

- Changes in driver layout requested by the eCos maintainers. This is just a reorganisation of the directory structure of the code. It should not change the functionality of the drivers.

- Removal of the ability to use the vanilla configtool rather than the nios2configtool wrapper when building for Nios II. This was a change requested by the eCos maintainers, and is intended to reduce the risk of confusion.

- Addition of a nios2ecosconfig wrapper to allow projects to be build from the command line rather than through the nios2configtool GUI.

- Removal of the unused boot stub in ROMRAM mode to allow applications to succesfully download through nios2-download.

- Provided replacment stub for the C++ exception terminate handler to allow eCos to build succesfully with the latest version of GCC.

- Reformatted the Redboot debug information to be compatible with the new version of GDB.

- Set the MicroWindows defaults to be more Nios II freindly.

- Increased the default web server stack size to avoid overflow when using DHCP.

- ROMRAM is now the default configuration rather than RAM.

- The license text was updated as requested by the eCos maintainers.

- Makefile changes were made to avoid unecessary regeneration of PTF dependent files (i.e. the linker script etc.) which had previously been slowing build times.

- The location of the Nios II host side tools was changed to be more consistent with other ports.

- Fixed RTC constant definitions to support more than just the default tick rate.