Pre-computed Detector database

[BSchelpe]

PR #573 implements Option 2 of Issue #509. Option 3 is still to be implemented, ie ship an already populated database along with tqec and modify the existing interface to implement a flexible hybrid of locally computed/stored and the pre-computed database.

[nelimee]

Depending on the size of the database, we might:

1. ship it with tqec, meaning that we should re-generate it when publishing, which is not a large issue because it is already generated with the tests in tqec.compile.compile_test.py.
2. provide is alongside tqec and download it when needed.

Option 1 is perfect as long as the database is not large, option 2 is better only if the database is large in size.