Basically, Gargantext.Prelude exports all of Protolude now.

FlowCmdM -> DBCmd or HasNodeStory is usually enough

- DBCmd instead of Cmd
- remove FlowCmdM in favor of HasNodeStory

This fixes commit 5d5300cd which
automatically changed all 'return' to 'pure' in our code, resulting in
broken SQL etc.

This commits changes the `PhyloData` data structure to
include a proper `GraphData` in the `pd_data` field. The
`GraphData` is almost complete, but the `objects` field needs
to be further refined from a generic JSON `Value` to proper
Haskell types.

This reverts commit a444cb30.

This reverts commit d04cf03b, reversing
changes made to e213a4bf.