Give useful staking info (#109)

* nextSession & nextEra w/o derive

Setup storage queries

clean up

Move queuedElected to not throw on isNone

get ready to delete some epoch arithmetic

Calculate nextExpectedEpochChange

save progress

* Use derived call for nextEra & nextSession

save progress

next session and next era

small cleanup

small fixes

reorganize a bit

* Calc toggle

initial window change working

clean up

make toggle hardcoded based on chainSpec

make query for activeEra, not derive

save before deleting sessionInfo derive stuff

toggle working; try/catch queueElected;

begin making deriveSessionProgress

deriveSessionProgress done, deleting old

refactor deriveElectionLookAhead, async fetchStakingInfo(hash: BlockHash): Promise<StakingInfo> {

q

add comments and move some things

more refining

correct era progress

clean up

pre squash

* Calc toggle

initial window change working

clean up

make toggle hardcoded based on...