Fix `else` block lint errors

auth.go

@@ -38,10 +38,8 @@ func (c *Client) LogIn(username, pass string) (*AuthUser, error) {
 		return nil, fmt.Errorf("User does not exist.")
 	} else if status == http.StatusTooManyRequests {
 		return nil, fmt.Errorf("Stop repeatedly trying to log in.")
-	} else {
-		return nil, fmt.Errorf("Problem authenticating: %s. %v\n", status, err)
 	}
-	return u, nil
+	return nil, fmt.Errorf("Problem authenticating: %s. %v\n", status, err)
 }
 
 func (c *Client) isNotLoggedIn(code int) bool {

collection.go

@@ -80,8 +80,6 @@ func (c *Client) CreateCollection(sp *CollectionParams) (*Collection, error) {
 		return nil, fmt.Errorf("Collection name is already taken.")
 	} else if status == http.StatusPreconditionFailed {
 		return nil, fmt.Errorf("Reached max collection quota.")
-	} else {
-		return nil, fmt.Errorf("Problem getting post: %s. %v\n", status, err)
 	}
-	return p, nil
+	return nil, fmt.Errorf("Problem getting post: %s. %v\n", status, err)
 }

post.go

@@ -81,10 +81,8 @@ func (c *Client) GetPost(id string) (*Post, error) {
 		return nil, fmt.Errorf("Post not found.")
 	} else if status == http.StatusGone {
 		return nil, fmt.Errorf("Post unpublished.")
-	} else {
-		return nil, fmt.Errorf("Problem getting post: %s. %v\n", status, err)
 	}
-	return p, nil
+	return nil, fmt.Errorf("Problem getting post: %s. %v\n", status, err)
 }
 
 // CreatePost publishes a new post, returning a user-friendly error if one comes
@@ -133,10 +131,8 @@ func (c *Client) UpdatePost(sp *PostParams) (*Post, error) {
 		return nil, fmt.Errorf("Not authenticated.")
 	} else if status == http.StatusBadRequest {
 		return nil, fmt.Errorf("Bad request: %s", env.ErrorMessage)
-	} else {
-		return nil, fmt.Errorf("Problem getting post: %s. %v\n", status, err)
 	}
-	return p, nil
+	return nil, fmt.Errorf("Problem getting post: %s. %v\n", status, err)
 }
 
 // DeletePost permanently deletes a published post. See