StateDB bringup

[ermo]

StateDB needs doing first in the new branch with .Installation knowing the current state pointer.

[ermo]

Here's what Ikey had to say about it:

ermo: Do you want some verbalisation time?
Ikey Doherty: nah i think its a simple enough matter
Ikey Doherty: StateDB is uint -> State
Ikey Doherty: and Installation needs to poke the state pointer
Ikey Doherty: so we can load the right one
Ikey Doherty: whereas before we loaded the current/next state in the DB and it was ugly
Ikey Doherty: by getting it from the filesystem it'll fix the rollback thing
Ikey Doherty: also we can keep an entire State with pkgIDs[] in memory now
Ikey Doherty: vs keep filtering/eaching it
ermo: (Narrator: Ikey did want some verbalisation time)
Ikey Doherty: XD

[ikeycode]

We have functioning StateDB - planning a DB break (sorry rootfs owners) to switch from string[] pkgID, to Selection

[ermo]

Ikey Doherty
As a matter of priority statedb needs fixing
This is a breaking change to installs
I.e. selection hints
Automatically installed manually selected etc
Statedb change is critical for upgrade logic
So can filter automatically installed stuff
And drop garbage
So IF pkgA depended on pkgB, an update happens and now pkgA depends on pkgC, THEN if pkgB is no longer needed, drop it