Delete description of Curve25519 usage that shouldn't be in the abstract section.

Signed-off-by: Daira Hopwood <daira@jacaranda.org>

protocol/protocol.tex

@@ -1230,23 +1230,6 @@ as follows:}
 \end{equation*}
 }
 
-\changed{
-where
-\begin{itemize}
-  \item $\CurveMultiply(\bytes{n}, \bytes{q})$ performs point
-multiplication of the Curve25519 public key represented by the byte
-sequence $\bytes{q}$ by the Curve25519 secret key represented by the
-byte sequence $\bytes{n}$, as defined in \cite[section 2]{Bern2006};
-  \item $\CurveBase$ is the public byte sequence representing the Curve25519
-base point;
-  \item $\Clamp(\bytes{x})$ takes a 32-byte sequence $\bytes{x}$ as input
-and returns a byte sequence representing a Curve25519 private key, with
-bits ``clamped'' as described in \cite[section 3]{Bern2006}:
-``clear bits $0, 1, 2$ of the first byte, clear bit $7$ of the last byte,
-and set bit $6$ of the last byte.'' Here the bits of a byte are numbered
-such that bit $b$ has numeric weight $2^b$.
-\end{itemize}
-}
 \nsubsection{Note Components}
 
 A \note consists of $(\AuthPublic, \Value, \NoteAddressRand, \NoteCommitRand)$ where