Update BUILDING.txt for latest version.
Merge pull request #99 from Hello71/building

Update BUILDING.txt for latest version.
cleanup and checks to avoid bad addresses

- removed obsolete name reads

#73 bad addresses:
- commented out unused prefix stuff in words
- checks for invalid materials before attempting to read
-
Use process_vm_{read,write}v instead of ptrace

This approximately doubles the speed of Dwarf Therapist on Linux, and
fixes #73.
Silence bad address errors.