Adding/editing swagger api docs

The api documentation is generated using swaggo from comments.

Documenting structs

You should always comment every field which will be exposed as a json in the api. These comments will show up in the documentation, it’ll make it easier for developers using the api.

As an example, this is the definition of a list with all comments:

// List represents a list of tasks
type List struct {
	// The unique, numeric id of this list.
	ID int64 `xorm:"int(11) autoincr not null unique pk" json:"id" param:"list"`
	// The title of the list. You'll see this in the namespace overview.
	Title string `xorm:"varchar(250)" json:"title" valid:"required,runelength(3|250)" minLength:"3" maxLength:"250"`
	// The description of the list.
	Description string `xorm:"varchar(1000)" json:"description" valid:"runelength(0|1000)" maxLength:"1000"`
	OwnerID     int64  `xorm:"int(11) INDEX" json:"-"`
	NamespaceID int64  `xorm:"int(11) INDEX" json:"-" param:"namespace"`

	// The user who created this list.
	Owner User `xorm:"-" json:"owner" valid:"-"`
	// An array of tasks which belong to the list.
	Tasks []*ListTask `xorm:"-" json:"tasks"`

	// A unix timestamp when this list was created. You cannot change this value.
	Created int64 `xorm:"created" json:"created"`
	// A unix timestamp when this list was last updated. You cannot change this value.
	Updated int64 `xorm:"updated" json:"updated"`

	web.CRUDable `xorm:"-" json:"-"`
	web.Rights   `xorm:"-" json:"-"`
}