Add type casting for Swagger UI configuration options

[glowcloud]

When the configuration options are defined in the URL query parameters, we are actually getting strings. This causes issues if the value of the configuration parameter should not be a string.

For example, for deepLinking we should actually have a boolean value, but instead we'll have a string "true". This means that this configuration option won't actually be activated.

To fix this, we need to cast values into proper types if we can, ex. for number and boolean. We won't be parsing object and array type values.

[char0n]

Le'ts concentrate the type casting int config/type-cast module. We will map path to the typecaster to make the design declarative.

const Boolean = (string) => boolean

Map
 - syntaxHighlight.activated: Boolean
 

We want to apply the typecasting as a last operation in the merge function.

[glowcloud]

Addressed in #9829

[glowcloud]

Released as https://github.com/swagger-api/swagger-ui/releases/tag/v5.16.0