Baconian cipher with any 2 symbols

[avyukth-fll]

edited encode and decode functions to support any 2 symbols.
Now, Encode function also can take 2 symbols as input, and the encoded cipher will use those 2 symbols.
Now, Decode function can also decode ciphers that use other symbols that aren't A & B , like E & F

[algorithms-keeper]

Closing this pull request as invalid

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