fix legacy bug and update to depend anki 2.1.36

[cecini]

• update ankisyncd _homepage
• enable V2 scheduler
• update dependency anki and ankirspy to 2.1.36(06292a45f304fc3c9ea2ef09789b090b2e368016),
  with patch align rslib get_subnode impl with anki pythonapi find_deck_in_tree #805
  align rslib get_subnode impl with anki pythonapi find_deck_in_tree ankitects/anki#805
  once not apply the patch , the nestdeck sync will fail,lead to recheck database errro on desktop.
  So you can only use the nonnestdeck without the patch.
• fix the remove deck lead server crash issue Sync crashes after deck deletion #28,change intruduced after 3.1.28 f592672fa
• fix: once client items in graves have been remove in the server,need update graves usn as maxusn
  avoid sync serve log: sanity check failed with server: graves had usn = -1 such as issue Sync crashes after deck deletion #28
  second comment
• fix client add then delete item then sync issue, deck/card/note must not been synced after client add
• ensure mediadir exsit in the case full sync ok after delete server collection dir

Note: Look like the bug intruduced after the 2.1.28, so the update dependency is not related with the bug fixed.

Now test to be working with anki 2.1.36 desktop , AnkiDroid 2.13.5.

[cecini]

Once client items in graves have been removed in the server, need update graves usn to current max usn.
The bug look like that set server=True is not working, initially use the self.col.db.execute("update graves set usn=? where usn=-1", self.maxUsn) to fix ,now use the chang the ankisyncserve boostrap way to open collection as server mode(to pass info to rsbackend), so the card/note/deck remove will add grave entry to the grave table and set usn as maxusn(in remove impl of rsbackend)

[VikashKothary]

Thank you for your contribution.

I still need to check your legacy bug fix but I've left some comments in the meantime. This PR also closes #31.

Also try and keep minor changes like the homepage change and version bumps as separate PRs because they'll get merged easier and quicker.

[liu-hz]

Do we need to adjust the version of anki when we upgrade it requirements.txt Then update the PIP tool library? Thank you very much for your continuous update and maintenance of anki upgrade. Thank you very much

[cecini]

@VikashKothary just split to small prs.
For your clarity:

• update ankisyncd _homepage Update ankisyncd _homepage #45
• enable V2 scheduler Enable V2 scheduler #46
• update dependency anki and ankirspy Update dep anki ankirspy to 2.1.36 and fix the requirments file create #47
• fix the remove deck lead server crash issue Sync crashes after deck deletion #28,change intruduced after 3.1.28 f592672fa Fix the remove deck lead server crash issue #28 #48
• fix: once client items in graves have been remove in the server,need update graves usn as maxusn Fix: server side graves's usn need not set as -1 #49
• fix client add then delete item then sync issue, deck/card/note must not been synced after client add Fix client add then delete item then sync issue #51
• ensure mediadir exsit in the case full sync ok after delete server collection dir Ensure mediadir exsit in the case full sync from client should be ok after delete server collection dir #50