Get rid of C99 PRI?64 usage in source files

Amend to d5f1e72. It turns out that BerkelyDB was including inttypes.h
indirectly, so we cannot fix this with just macros.

Trivial commit: apply the following script to all .cpp and .h files:

    # Middle
    sed -i 's/"PRIx64"/x/g' "$1"
    sed -i 's/"PRIu64"/u/g' "$1"
    sed -i 's/"PRId64"/d/g' "$1"
    # Initial
    sed -i 's/PRIx64"/"x/g' "$1"
    sed -i 's/PRIu64"/"u/g' "$1"
    sed -i 's/PRId64"/"d/g' "$1"
    # Trailing
    sed -i 's/"PRIx64/x"/g' "$1"
    sed -i 's/"PRIu64/u"/g' "$1"
    sed -i 's/"PRId64/d"/g' "$1"

After this commit, `git grep` for PRI.64 should turn up nothing except
the defines in util.h.
Remove definition of PRI?64 in util.h

This was a bad idea. This can't be solved with macros as any
other library that includes inttypes.h will get in the way.

The parent commit has removed all usages from the source, this commit
removes the definition.
Merge pull request #3735 from laanwj/2014_02_remove_PRIx64_completely

Remove PRIx64 usage completely