Improve paragraph spacing and remove paragraph indent.

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

protocol/protocol.tex

@@ -11,6 +11,8 @@
 \setlength{\textwidth}{7in}   % Right margin of 8.5 in - 1 in - 6.5 in = 1 in
 \setlength{\topmargin}{-.75in}  % Top margin of 2 in -0.75 in = 1 in
 \setlength{\textheight}{9.2in}  % Lower margin of 11 in - 9 in - 1 in = 1 in
+\setlength{\parskip}{1.5ex}
+\setlength{\parindent}{0ex}
 
 \mathchardef\mhyphen="2D
 
@@ -188,14 +190,10 @@ the trailing (final) $k$ bits of its input.
 
 \subsection{Cryptographic Functions}
 
-\subparagraph{}
-
 $\CRH$ is a collision-resistant hash function. In \Zcash, the $\SHAName$ function
 is used which takes a 512-bit block and produces a 256-bit hash. This is
 different from the $\SHAOrig$ function, which hashes arbitrary-length strings.
 
-\subparagraph{}
-
 $\PRF{x}{}$ is a pseudo-random function seeded by $x$. Three \emph{independent}
 $\PRF{x}{}$ are needed in our scheme: $\PRFaddr{x}$, $\PRFsn{x}$, and $\PRFpk{x}$.
 It is required that $\PRFsn{x}$ be collision-resistant across all $x$ --- i.e. it
@@ -251,8 +249,6 @@ independent.
 
 \subsection{Confidential Addresses and Private Keys}
 
-\subparagraph{}
-
 A key pair $(\PublicAddress, \PrivateAddress)$ is generated by users who wish to
 receive coins under this scheme. The public $\PublicAddress$ is called a
 $\publicAddress$ and is a tuple $(\SpendAuthorityPublic, \TransmitPublic)$
@@ -263,8 +259,6 @@ a $\privateAddress$ and is a tuple $(\SpendAuthorityPrivate, \TransmitPrivate)$
 consisting of the respective \emph{private} components of the aforementioned
 $\spendAuthority$ and $\transmitPublicAlgorithm$ key pairs.
 
-\subparagraph{}
-
 Although users can accept payment from multiple parties with a single
 $\PublicAddress$ without either party being aware, it is still recommended to
 generate a new address for each expected transaction to maximize privacy in the
@@ -272,8 +266,6 @@ event that multiple sending parties are compromised or collude.
 
 \subsection{Coins}
 
-\subparagraph{}
-
 A \coin (denoted $\Coin$) is a tuple $(\SpendAuthorityPublic, \Value,
 \CoinAddressRand, \CoinCommitRand)$ which represents that a value $\Value$ is
 spendable by the recipient who holds the $\spendAuthority$ key pair
@@ -345,24 +337,18 @@ disclosing $\sn$, allowing $\sn$ to be used to prevent double-spending.
 \includegraphics[scale=.4]{incremental_merkle}
 \end{center}
 
-\subparagraph{}
-
 The \coinCommitmentTree is an \incrementalMerkleTree of depth $\MerkleDepth$ used to
 store \coinCommitments that \PourTransfers produce. Just as the \term{unspent
 transaction output set} (UTXO) used in Bitcoin, it is used to express the existence
 of value and the capability to spend it. However, unlike the UTXO, it is \emph{not}
 the job of this tree to protect against double-spending, as it is append-only.
 
-\subparagraph{}
-
 Blocks in the blockchain are associated (by all nodes) with the root of this tree
 after all of its constituent \PourDescriptions' \coinCommitments have been
 entered into the tree associated with the previous block.
 
 \subsection{Spent Serials Map}
 
-\subparagraph{}
-
 Transactions insert \serialNumbers into a \spentSerialsMap which is maintained 
 alongside the UTXO by all nodes.
 
@@ -505,12 +491,8 @@ exists in the map.
 
 \subsection{Pour Circuit and Proofs}
 
-\subparagraph{}
-
 In \Zcash, $\NOld$ and $\NNew$ are both $2$.
 
-\subparagraph{}
-
 A valid instance of $\PourProof$ assures that given a \term{primary input}
 $(\rt, \snOld{1..\NOld}, \cmNew{1..\NNew}, \vpubOld, \vpubNew, \hSig, \h{1..\NOld})$,
 a witness of \term{auxiliary input}