Spec: Clarify when bit reading is done.

- Addresses a comment in KhronosGroup/glTF#1114

docs/spec/04.00.00.conventions.md

@@ -54,7 +54,7 @@ section is the header. The second section contains the metadata. This section is
 
 * f[n]
   * Unsigned n-bit number appearing directly in the bitstream. The bits are read from high to low order.
-  * When bit reading is finished it will always pad the read to the current byte.
+  * When bit reading is finished it will always pad the read to the current byte. ResetBitReader() will signify when the bit reading is finished.
 
 * I16, UI16, I32, UI32, I64, UI64, and Float values must be little endian.
 

docs/spec/edgebreaker.decoder.md

@@ -28,6 +28,7 @@ void ParseTopologySplitEvents() {
   for (i = 0; i < num_topology_splits; ++i) {
     source_edge_bit[i]                                                                f[1]
   }
+  ResetBitReader();
 }
 ~~~~~
 {:.draco-syntax }

docs/spec/rans.decoding.md

@@ -32,6 +32,7 @@ void DecodeTaggedSymbols(num_values, num_components, out_values) {
       val                                                                             f[size]
       out_values.push_back(val);
     }
+    ResetBitReader();
   }
 }
 ~~~~~