Change RTT behavior with respect to summary lengths

RTT will avoid processing a Ricardian contract if the length of the raw summary is greater than 116 characters.

Furthermore, if the generated summary is greater than 116 characters, RTT will simply truncate the generated summary string to fit. I consider this truncation to be a bug: if the spec required the generated string to be no more than 116 character (which I'm not sure if it does because it is ambiguously worded) then it should not return any successful result. But I think it would be better for the library to just return the full generated string, however long it is, and allow the authenticate UI to enforce any truncation it wants.

Better yet, if this (EOSIO/ricardian-spec#20) proposed change to the Ricardian spec is adopted, then RTT should not enforce any limit on the summary. Such a limit could optionally be enforced in the authenticator UI.

Start by reading the RTT summary-length behavior described here and compare it with the proposed change in EOSIO/ricardian-spec#20. Resolve whether the 116-character limit belongs in RTT or the authenticator UI, then verify that raw summaries, generated summaries, and oversized results follow the chosen policy without silent truncation.

Written by the indexing model from the issue text.