Add support to other EDICT2 dictionaries

[GrimPixel]

I was trying to convert HanDeDict and CC-CEDICT was selected automatically. Then I got

raceback (most recent call last):
  File "/home/user/venv/lib/python3.12/site-packages/pyglossary/glossary_v2.py", line 570, in _openReader
    openResult = reader.open(filename)
                 ^^^^^^^^^^^^^^^^^^^^^
  File "/home/grim/venv/lib/python3.12/site-packages/pyglossary/plugins/cc_cedict/__init__.py", line 68, in open
    raise RuntimeError("CC-CEDICT: could not find entry count")
RuntimeError: CC-CEDICT: could not find entry count

[CRITICAL] Reading file 'Downloads/handedict.u8' failed.

As far as I know, the format of CC-CEDICT is EDICT2. There are several sources of this type and I haven't tried converting them:

• CC-Canto
• CFDICT
• HanDeDict
• CHDICT
• Wadoku
• Waran Jiten

So I guess that CC-CEDICT can be renamed to EDICT2, when those dictionaries above can be converted without problem?