make dev builds -O1

possible fix for #75 (closed)

At first I tried to -O1 only a few crates, but there are actually many that appear to be quite bad in a flamegraph timing just the startup. Non exhaustive list:

• keccak
• sha2
• tor_llcrypto
• tor_netdoc
• rangemap
• base64ct
• core
• alloc
• ...
  and to a lesser point, subtle, hex....

by I don't know which magic, trying to build just these with

[profile.dev.package.<name>]
opt-level = 1

seemed to have a negligible effect, but -O1 the whole build makes loading microdescs go from ~17s to ~3s on my laptop (at the cost of doubling compilation time)