This commit adds a configuration option for the webAllowOthers option for the H2 WebServlet. It will only be added it the spring.h2.console.webAllowOthers is set to true, else it will be ignored.

Fixes: gh-5416

I've signed the Spring ICLA.

Comment From: snicoll

My gut feeling is that we should have a separate namespace for init parameters. But on the other hand, it's quite specific already. You know you can put that setting in the home directory right?

Comment From: wilkinsona

See also #5234

Comment From: mdeinum

@snicoll I know I can put the setting in the home directory but I like the fact that the properties are in a single place and not "scattered" around. It also allows me to easily pickup the jar and drop it somewhere else, without forgetting to copy the file from the home directory.

I like the idea however of having a separate namespace especially if this would work on a global level allowing to specify init-params for every ServletRegistrationBean in the context.

Comment From: snicoll

Merged with a polish commit (bca83bd). Thanks again!