Mistake in Exception message

[TheNetworkIsDown]

The actual function to be called would be initLayout(), not setLayout(), which does not exist.

[update-docs]

Thanks for opening this pull request! The maintainers of this repository would appreciate it if you would update some of our documentation based on your changes.

[codecov]

Codecov Report

Merging #975 into develop will not change coverage.
The diff coverage is 0%.

@@            Coverage Diff             @@
##             develop     #975   +/-   ##
==========================================
  Coverage      71.42%   71.42%           
  Complexity      2663     2663           
==========================================
  Files            126      126           
  Lines           6254     6254           
==========================================
  Hits            4467     4467           
  Misses          1787     1787

Impacted Files	Coverage Δ	Complexity Δ
src/App.php	79.16% <0%> (ø)	138 <0> (ø)	⬇️

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[abbadon1334]

yes, good catch!
but now can be much better to divide the error from the solution like this :

$e = new Exception('App layout is missing');
$e->addSolution('If you use $app->add() you should first call $app->setLayout()');
throw $e;

[DarkSide666]

There are actually more mentions of setLayout in docs and source code. I will fix that too afterwards.
Thanks!

Edit: I will create and merge new PR instead of this because I'm unable to add anything to your branch. There should be more fixes there.