Validators gain/lose value during their 2 dynasty waiting period

[djrtwo]

Issue

@yzhang90 pointed out that because a validator's deposit is scaled at current_epoch when they make a deposit but that they don't get to participate in consensus until 2 dynasties from then (at least two epochs), the validator has a period of time in which they gain/lose ether but cannot participate in consensus.

Proposed Implementation [UNFINISHED]

The below proposal is incomplete
Instead of storing a scaled ether deposit when the validator logs in, just store the raw ether, scaling by both the start_dynasty and end_dynasty scale factor when relevant (withdrawal`).

This works for the individual deposits but does not solve the issue for dynasty_wei_delta.

[djrtwo]

@karlfloersch @vbuterin @ChihChengLiang Requesting your comments on the above issue.

[ChihChengLiang]

Just thinking out loud. So during these 2 dynasties, the validator loses deposit due to not voting. but should be able to earn back after few more dynasties.
If we want to patch it, should we have a temporary deposit that becomes real deposit after start_dynasty and is not getting rescaled before start_dynasty?