Four player adapter edits (#618)

* Four Player Adapter: fix broken tables

On the rendered pandocs site some of the Four Player Adapter page tables appear broken (showing up as markdown source). I think because they are missing blank lines above the tables. This attempts to fix that.

* Four Player Adapter: fix typo

"by" not "byte"

Author: bbbbbr

src/Four_Player_Adapter.md

@@ -54,6 +54,7 @@ a little more time than a single Game Boy video frame.
 ### Ping Packet Fields
 
 The ping data received by each Game Boy looks like this:
+
 Byte | Value | Description
 -----|-------|-------------
   1  | \$FE  | PING HEADER
@@ -62,6 +63,7 @@ Byte | Value | Description
   4  |   ??  | STAT3
 
 The chart below illustrates how Game Boys should respond to bytes in a ping packet:
+
 Received From DMG-07 | Game Boy Reply
 ---------------------|-----------------------
 PING HEADER (\$FE)   | ACK1 = (\$88)
@@ -135,6 +137,7 @@ the Game Boys. Each byte is usually the same, however, sometimes the status can
 change midway through a ping, typically on STAT2 or STAT3. 
 
 Each STAT byte has the following fields:
+
 Bit | Name
 ----|------------------------
  7  | Player 4 Connected
@@ -156,7 +159,8 @@ The upper-half of STAT1, STAT2, and STAT3 are updated based on the ping response
 to show when Game Boys are "connected". If for whatever reason, the ping responses
 are not sent, the status bits are unset.
 
-Some examples of ping packets sent byte the DMG-07 are shown below:
+Some examples of ping packets sent by the DMG-07 are shown below:
+
 Packet        | Description
 --------------|-------------------------------------------------------
 `FE 01 01 01` | Ping packet received by Player 1 with no other Game Boys connected.