Specifying Values for Common Parameters

[SvenEV]

Some parameters (e.g. for "Authorization" header) appear in multiple or even all operations of a Swagger document. There should be an area in the app that lists such common parameters and allows the user to specify arguments that are then used in all corresponding operations.

Open questions:

• What makes a parameter "common"? Existence in all operations or in >XX% of operations? Maybe every parameter can be assigned a "default"/"common" value and we just provide some suggestions.

[SvenEV]

Done in c3f8f41. For now, all parameters are listed in the "Global Arguments" section, even if they only appear in one or very few operation.