blockchain: updated store docs/comments from review

blockchain/store.go

@@ -35,8 +35,8 @@ type BlockStore struct {
 	height int64
 }
 
-// NewBlockStore returns a new BlockStore with the given db,
-// initialized to the last committed height.
+// NewBlockStore returns a new BlockStore with the given DB,
+// initialized to the last height that was committed to the DB.
 func NewBlockStore(db dbm.DB) *BlockStore {
 	bsjson := LoadBlockStoreStateJSON(db)
 	return &BlockStore{
@@ -54,7 +54,7 @@ func (bs *BlockStore) Height() int64 {
 
 // GetReader returns the value associated with the given key wrapped in an io.Reader.
 // If no value is found, it returns nil.
-// Its mainly for use with wire.ReadBinary.
+// It's mainly for use with wire.ReadBinary.
 func (bs *BlockStore) GetReader(key []byte) io.Reader {
 	bytez := bs.db.Get(key)
 	if bytez == nil {
@@ -249,7 +249,7 @@ func (bsj BlockStoreStateJSON) Save(db dbm.DB) {
 }
 
 // LoadBlockStoreStateJSON returns the BlockStoreStateJSON as loaded from disk.
-// If no BlockStoreStateJSON was previously persisted, it returns a zero value one.
+// If no BlockStoreStateJSON was previously persisted, it returns the zero value.
 func LoadBlockStoreStateJSON(db dbm.DB) BlockStoreStateJSON {
 	bytes := db.Get(blockStoreKey)
 	if bytes == nil {