Exclusion keyword for armor type keyword distribution

[ProbablyManuel]

Since in vanilla Skyrim shields do not have an armor type keyword, the Reqtificator assigns the missing keyword to all armors based on the armor type. However, this causes problems with bound armors that must have an armor type so that they can receive armor rating, even though they are not supposed to be treated as armors.

Expected Outcome

• Armors with the keyword RFTI_Exclusions_NoArmorTypeKeyword do not receive an armor type keyword.
• The new keyword is added to the Keyword Reference documentation.