lint: Check that all wallet args are hidden #15920

Can be tested by calling git revert 765d5890be and then running the script

utACK fac174e

$ merge 15920
[pull/15920/local-merge d4663cc6a] Merge [#15920](/bitcoin-bitcoin/15920/): lint: Check that all wallet args are hidden
 Date: Mon Apr 29 20:50:41 2019 +0800
[#15920](/bitcoin-bitcoin/15920/) lint: Check that all wallet args are hidden into master
* fac174e2d lint: Check that all wallet args are hidden (MarcoFalke) (pull/15920/head)

Dropping you on a shell so you can try building/testing the merged source.
Run 'git diff HEAD~' to show the changes being merged.
Type 'exit' when done.

bash-3.2$ git revert 765d5890be
[pull/15920/local-merge c8412b746] Revert "Bugfix: dummywallet: Add -ignorepartialspends to list of ignored wallet options"
 1 file changed, 1 deletion(-)

bash-3.2$ test/lint/check-doc.py
Args used        : 175
Args documented  : 183
Args undocumented: 0
set()
Args unknown     : 8
{'-zmqpubhashtxhwm', '-zmqpubrawtxhwm', '-zmqpubhashtx', '-zmqpubrawblock', '-zmqpubrawblockhwm', '-zmqpubrawtx', '-zmqpubhashblockhwm', '-zmqpubhashblock'}
Traceback (most recent call last):
  File "test/lint/check-doc.py", line 66, in <module>
    main()
  File "test/lint/check-doc.py", line 62, in main
    lint_missing_hidden_wallet_args()
  File "test/lint/check-doc.py", line 57, in lint_missing_hidden_wallet_args
    assert 0, "Please add {} to the hidden args in DummyWalletInit::AddWalletOptions".format(hidden_missing)
AssertionError: Please add {'-avoidpartialspends'} to the hidden args in DummyWalletInit::AddWalletOptions

bash-3.2$ git revert c8412b746
[pull/15920/local-merge c40e287ad] Revert "Revert "Bugfix: dummywallet: Add -ignorepartialspends to list of ignored wallet options""
 1 file changed, 1 insertion(+)

bash-3.2$ test/lint/check-doc.py
Args used        : 175
Args documented  : 183
Args undocumented: 0
set()
Args unknown     : 8
{'-zmqpubhashblockhwm', '-zmqpubrawtxhwm', '-zmqpubhashblock', '-zmqpubhashtx', '-zmqpubrawblockhwm', '-zmqpubrawblock', '-zmqpubrawtx', '-zmqpubhashtxhwm'}

tACK fac174e2d17e06b63aa5eb20b404af00d38db26e

Very nice to have a linter making sure that reviewers never have to think about this ever again :-) @fanquake Out of curiosity: what merge alias/script (merge 15920 in your the shell session you posted) do you use to easily check out the PR locally? I've written such an alias/script myself for my needs but I'd rather use a less hacky packaged alias/script if available :-)

@practicalswift It's the github-merge.py script in contrib/devtools.

@practicalswift Linters are NOT a substitute for proper review!

@luke-jr No, obviously not. Linters complement proper human review. Ideally they catch errors before any human review takes place.