Some bugs in the Nemeth arrow translations

[NSoiffer]

I see two blocks with similar (in each block) errors:

These four arrow entries are wrong:

 - "⇠": [t: "⠫⠪⠒⠒"]             # 0x21e0
 - "⇡": [t: "⠫⠣⠒⠒⠕"]            # 0x21e1
 - "⇢": [t: "⠫⠒⠒⠕"]             # 0x21e2
 - "⇣": [t: "⠫⠩⠒⠒⠕"]            # 0x21e3

Because they are dashed, they are supposed to have a space in them. For example

  - "⇡": [t: "⠫⠣⠒⠀⠒⠕"]            # 0x21e1

The other group of errors involves doubling up the arrow tips instead of the arrow shafts. The first entry below is correct but the others are wrong. I don't know how you would represent the last two that have a triple arrow shaft as I don't see a way to do that in Nemeth (but I may have missed something)

 - "⇐": [t: "⠫⠪⠶⠶"]             # 0x21d0
 - "⇑": [t: "⠫⠣⠒⠒⠕⠕"]           # 0x21d1
 - "⇒": [t: "⠫⠒⠒⠕⠕"]            # 0x21d2
 - "⇓": [t: "⠫⠣⠒⠒⠕⠕"]           # 0x21d3
 - "⇔": [t: "⠫⠪⠪⠒⠒⠕⠕"]          # 0x21d4
 - "⇕": [t: "⠫⠣⠪⠪⠒⠒⠕⠕"]         # 0x21d5
 - "⇖": [t: "⠫⠘⠪⠪⠒⠒"]           # 0x21d6
 - "⇗": [t: "⠫⠘⠒⠒⠕⠕"]           # 0x21d7
 - "⇘": [t: "⠫⠰⠒⠒⠕⠕"]           # 0x21d8
 - "⇙": [t: "⠫⠰⠪⠪⠒⠒"]           # 0x21d9
 - "⇚": [t: "⠫⠪⠪⠪⠒⠒"]           # 0x21da
 - "⇛": [t: "⠫⠒⠒⠕⠕⠕"]           # 0x21db

If you uncover other problems in the character translations, I'd appreciate it if you would let me know so I can update my tables. Thanks