ref: 8a516e9e064619dcb3d84499b66e1562546be918 xmpp/form d---------
all: update copyright message

[ci skip]
all: rewrap copyright comments/use xml.TokenReader
Shutup golint.

[ci skip]
form: rename "varName" to "id"
form: Rename Option and FieldOption types

Renamed to "Field" and "Option" respectively.
form: Add namespace constant
form: Fix broken options
form: Factor out new field construction
form: Add unstable API warning to docs
form: Make Required show up under options in docs
Start outlining a potential data forms API