Update netscript documentation.

Unfortunately, I haven't used most of the specialty APIs yet, so I'm not intimately familiar with where their documentation might be wrong. I figured some fixes were better than no fixes, and I can always make more fixes later.

Fixes #1023.

doc/source/netscript/advancedfunctions/getBitNodeMultipliers.rst

@@ -5,13 +5,16 @@ getBitNodeMultipliers() Netscript Function
 
     :RAM cost: 4 GB
 
-    Returns an object containing the current BitNode multipliers. This function
-    requires Source-File 5 in order to run. The multipliers are returned in
-    decimal forms (e.g. 1.5 instead of 150%). The multipliers represent the
-    difference between the current BitNode and the original BitNode (BitNode-1).
-    For example, if the *CrimeMoney* multiplier has a value of 0.1, then that
-    means that committing crimes in the current BitNode will only give 10% of
-    the money you would have received in BitNode-1.
+    If you are not in BitNode-5, then you must have Source-File 5-1 in order to
+    run this function.
+
+    Returns an object containing the current BitNode multipliers. The
+    multipliers are returned in decimal forms (e.g. 1.5 instead of 150%). The
+    multipliers represent the difference between the current BitNode and the
+    original BitNode (BitNode-1). For example, if the *CrimeMoney* multiplier
+    has a value of 0.1, then that means that committing crimes in the current
+    BitNode will only give 10% of the money you would have received in
+    BitNode-1.
 
     The structure of the returned object is subject to change as BitNode
     multipliers get added to the game. Refer to the `source code here