change votes per token PoS param to be per smallest denomination

[tzemanovic]

depends on #386

In genesis, we want to configure the votes_per_token to be 1/100 vote per namnam. Currently, it's calculated from whole tokens, so we want to change to be able express votes per nano tokens (in parts-per-billion instead of basis points).

Note that our total staked whole tokens will be capped at around i64::MAX / 8 / 10^7 = 115_292_150_460 (tendermint total voting power has upper limit of i64::MAX / 8) (related issue #159)

[brentstone]

I'm wondering if we may have an issue in the above case by storing namnam as a u64. If the maximum whole staked tokens is capped at 115_292_150_460, then let's say the max namnam is 115_292_150_460_000_000_000, but this is about 6.25 times the value of u64::MAX. Perhaps an easy fix could be to increase the votes_per_token.

[tzemanovic]

closing as #386 not gonna be implemented