Added setting for formatting enum keys in pascal case

[jrparish]

Our API team likes to use UNDERSCORE_CASE enums, but UI team prefers the more readable pascal casing.

This adds an optional setting to format the keys accordingly.

[vojtechhabarta]

Thanks for this feature. I think it is nice so I am merging it but I will push few changes.

Firstly I am adding enumMemberCasing parameter (instead of special parameter for Pascal case). This parameter can support not only "PascalCase" but also "camelCase" and possibly others. Since configuration parameters should be usable from build plugins (Maven, Gradle) I am adding this new parameter there as well. There is also description which is used when generating documentation. Here is an example of usage from Maven:

<configuration>
    ...
    <mapEnum>asEnum</mapEnum>
    <enumMemberCasing>PascalCase</enumMemberCasing>
    ...
</configuration>

Next are some improvements in splitting identifier into words using regular expression. It should now support letters other than A-Z and numbers should be treated as words. I am still not sure it supports all cases well but at least I added unit test specifically for this part so we can easily test and improve other cases.

Could you please check my changes if the feature works as expected?

[jrparish]

That looks great, thank you!

[vojtechhabarta]

Released in v2.28.785.