fixed Document.reload

[Catstyle]

use obj._data instead of self._fields_ordered since DynamicDocument missing some attributes

[landscape-bot]

Repository health decreased by 0.02% when pulling ab615b8 on Catstyle:issue/dynamic_document_reload into 1e930fe on MongoEngine:master.

• 1 new problem was found (including 0 errors and 1 code smell).
• No problems were fixed.

[Catstyle]

PR for #1050

[MRigal]

Good job @Catstyle ! Let me just think if this could have counter-effects on non-fields attribute for non-dynamic documents. If not, it looks good to merge to me

[amcgregor]

Thank the gods, this is something that I actually frequently ran into, but never had the time to track down. EmbeddedDocument support seems to have gotten quite borked at some point in the recent past. I'll have to check if this fixes the "embedded document has no field '_id'" errors I've been seeing.

[landscape-bot]

Repository health decreased by 0.02% when pulling 6a9f27e on Catstyle:issue/dynamic_document_reload into 9671ca5 on MongoEngine:master.

• 1 new problem was found (including 0 errors and 1 code smell).
• No problems were fixed.

[Catstyle]

rebased
but i have no idea why the test case failed

[MRigal]

passed, it wasn't because of you ;)

[touilleMan]

Merged

[touilleMan]

@thedrow I werged this PR (see a6a1021, ba0934e and 7580383)

However, the PR was in conflict so I had to merge it by hand instead of use github's automerging. I rewrote commit 6a9f27e (the one in conflict) into 7580383. I guess it's the reason github didn't realised the merge has been done.

I can revert my changes if you see a better way of doing this 👍