Revert "rm all in src/tools/"

This reverts commit beb760ad899b844d01681a9055270824e6087e8c.
Revert "Let data generation tools be under data/src"

This reverts commit 045555618262ce0f1394be3d7d3d37ee76977c02.
Don't recursively make src/tools. Reference:

http://aegis.sourceforge.net/auug97.pdf
Let src/tools/ recursively make data/ after init_database.

Issue: data/ cannot automatically check and build init_database.