Improvements:

. GCC4 is now the default default toolchain.
 GCC3 is still available (only for Windows 8 or older versions).
. Document new GASP ADP.
. Added sub-sections management in all linker script files (for GCC4).
. Stacked variables: Display RAM address rather than just offset from
 frame/stack pointer.
. Detect and report empty linker script file name.
. Install isn't possible anymore if the GNU directory is present to
 avoid GCC3/GCC4 mix.

Fixes:

. Remove persistent error messages after programming but not debugging.
. Cleanup "bad breakpoint" issues management.
. Remove GCC4 warning about "fast_cwd" in Windows 10.
. Hide peripheral bits that are not in EM6819xx-B300 devices.
. GCC4 properly supports 'section' attribute: Non page0 section
 variables are now correctly indirectly accessed.
. GCC4: Added attribute page0 as an alias to page_0 and attribute data
 as an alias to indirect.
. GCC4: Compiler didn't generate accurate debug information (Dwarf) for
 stacked variables.
. GCC4: Added missing segment information for some variables.