Update ch07.asciidoc

refactored text to create sizeable tip box; fixed typos

ch07.asciidoc

@@ -177,11 +177,11 @@ If the redeem script hash matches, the unlocking script is executed on its own,
 <Sig1> <Sig2> 2 PK1 PK2 PK3 PK4 PK5 5 CHECKMULTISIG
 ----
 
+Almost all the scripts described in this chapter can only be implemented as P2SH scripts. For example, a 2 of 5 standard multisignature locking script cannot be used directly in the locking script of an UTXO, as +IsStandard()+ would invalidate the transaction. To conform, a P2SH locking script can be used instead, as seen above. A transaction that then includes a P2SH unlocking script can be used to redeem this UTXO and will be valid so long as it does not contain more than 15 public keys. ((("", startref="mohamseven")))
+
 [TIP]
 ====
-Remember, because of policy set forth by the +IsStandard()+ function at the time of this writing, standard multisignature scripts are limited to at most 3 listed public keys, while P2SH are limited to at most 15 public keys. Standard multisignature scripts can invalidate transactions by way of their locking +or+ unlocking script, while P2SH can invalidate transactions by way of their unlocking script +only+. This is because there is no way for +IsStandard()+ to tell if a hash of a redeem script in a locking script includes more signatures than the currenetly imposed size limitation, so it can only observe the unlocking scripts in transaction inputs. 
-
-Almost all the scripts described in this chapter can only be implemented as P2SH scripts. For example, a 2 of 5 standard multisignature locking script cannot be used directly in the locking script of an UTXO, as +IsStandard()+ would invalidate the transaction. To conform, a P2SH locking script can be used instead, as seen above. A transaction that then includes a P2SH unlocking script can be used to redeem this UTXO and will be valid so long as it does not contain more than 15 public keys. ((("", startref="mohamseven")))
+Remember, because of policy set forth by the +IsStandard()+ function at the time of this writing, standard multisignature scripts are limited to at most 3 listed public keys, while P2SH are limited to at most 15 listed public keys. Standard multisignature scripts can invalidate transactions by way of their locking +or+ unlocking script, while P2SH can invalidate transactions by way of their unlocking script +only+. This is because there is no way for +IsStandard()+ to tell if a hash of a redeem script in a locking script includes more signatures than the currently imposed size limitation, so it can only observe the unlocking scripts in transaction inputs. 
 ====
 
 ==== P2SH Addresses