Suzhou numerals glyphs are still not redesigned; and 々,乄 needs to be redesigned in CN Subset, etc.

### Prerequisites

* [x] If you are reporting an issue that affects glyphs for characters for a particular region or regions, did you verify that the characters are within the supported scope of the region or regions? This generally means GB 18030 or Tōngyòng Guīfàn Hànzìbiǎo (通用规范汉字表) for China, Big Five or CNS 11643 Planes 1 & 2 for Taiwan, HKSCS-2016 for Hong Kong, the JIS standards for Japan, and KS X 1001 and KS X 1002 for Korea.

* [x] Did you thoroughly search the [open](https://github.com/adobe-fonts/source-han-serif/issues) and [closed](https://github.com/adobe-fonts/source-han-serif/issues?q=is%3Aissue+is%3Aclosed) issues to avoid reporting a duplicate issue?
* [x] Did you go through the [official font readme file](https://github.com/adobe-fonts/source-han-serif/raw/release/SourceHanSerifReadMe.pdf) to better understand the scope of the project, to include the *Known Issues* section at the very end?

### Description

#### 苏州码子〡〢〣〤〥〦〧〨〩
As per https://github.com/adobe-fonts/source-han-serif/issues/36#issuecomment-294324152 (2017-4-16, over the years @kenlunde ).

因为〥太难看了，我已经调整成不那么难看的，修正了〦〧的写法，且自制为一组字重可变字体（放在https://github.com/MY1L/HanItalic ）
（HanItalic）

另外〩的写法可能接近ㄆ（因为速写用途像夂连笔，不拆分4笔来写）而不是攵，实物参考：https://www.zhihu.com/question/19633798/answer/305401974
同时希望添加一个opentype特性如`calt`，在〡〢〣连续相连时，次一个字符间隔转为横写（一二三），例如`〢二〢二`（2222）

> 补充，苏州码子特性我已经写了现成的：https://github.com/MY1L/HanItalic/releases/tag/SrcMing

#### 楷体々乄
思源宋里假名和日本符号做成毛笔风格（楷体）可以理解，但在CN Subset里，这些符号一般不用楷体形式。
不仅不搭配，还会导致误认是否用错了楷体。
尤其々虽从日文引入，但这个符号在大陆字体几乎不用楷体表现，包括日本报纸里々也有宋体形式，这里有例子（https://www.zhihu.com/question/362825003 ）。考虑到与CJK扩B汉字𠚤(U+206A4)重复，可以在字体里复用同一字形，类似康熙部首的处理。
（HanItalic）

希望在CN区域能通过opentype特性`locl`自动将々调整为宋体。
我已经做好了，也放在上述自制字体里。

为什么CJK基本区的乄(U+4E44，⿻㇢㇔)做成楷体的？这又不是〆(U+3006)，写法不一样。

#### 㐃
U+3403㐃这个字符的粗体看上去是错误的，不符宋体形式。
我已经做了一个，也放在上述自制字体里。