code: public StrBuilder append(final boolean value) {
          if (value) {
              ensureCapacity(size + 4);
              buffer[size++] = 't';
              buffer[size++] = 'r';
              buffer[size++] = 'u';
              buffer[size++] = 'e';
          } else {
              ensureCapacity(size + 5);
              buffer[size++] = 'f';
              buffer[size++] = 'a';
              buffer[size++] = 'l';
              buffer[size++] = 's';
              buffer[size++] = 'e';
          }
          return this;
      }
docs: Appends a boolean value to the string builder.
  
  @param value  the value to append
  @return this, to enable chaining