Check return value from _conv["k"] and treat it

- fix kakasi.py to check return value
- change to avoid error for canConvert in k2a
- add comments to remember problem.
fix Nakaten: 0x30fb
pykakasi: deal with KUTOTEN-u3001/u3002
deal with u30fc and word page
fix u3095-u309f to skip
fix error

- k2a: avoid infinite loop
- fix syntax error
fix katakana dict

-katakana punctuation
-katakana special letters
Merge pull request #9 from miurahr/fix_infinite_loop

Fix infinite loop in Kana data