Update master branch version to 0.6

As I start to work on MRI updates, it makes sense to update the library
version fields.
Remove Packet_Init() function

It makes more sense for Packet_GetFromGDB() and Packet_SendToGDB() to
just initialize the Packet structure as needed rather than making the
caller do this work.

This change was made during my code review of the MRI code base.
Small cleanup from MRI code review

Just added a missing space in gdb_console.c and moved a static function
around in token.c to place it closer to its first usage.