Fix Vigenere Bug

[CameronLonsdale]

Not sure why, but this does not get decrypted properly

N VVWJN ENB A PWINRG ITNNG WE VEEKRWAEG VW FRCQJL WICJN. GPR OUAKGROAA BO A AQASA VVPUUQMQ NSCQBWATM, QNCRXGROA, IAM SHZCAIFM NCTNKXB. TUMVA CBDRAT ZMGQOQA BO WNOVWG VZENGHTNA WNZSJRR ERAE QMRVEQ LVBHBVBAAOTR JNQ JRWENBU CHR PBWOE WS CHR ANVUEIV. CHBCTQ SUQAXBV XEXPRZ, NB SCMPRAYTL CRNQAND FXVNS NVQ VEEKRWAEQRB, ACXRJRRL VW TUM 15GQ CRVGDRL LHAIAO GQE FMAPOXC CNRVWQ (15CH–17GP PNNGCEREF), IACEPMQNNGA ZJY UIIN EKQFCEQ IF NAETL JS GPR 12CH PMACUEG."

Also, you should get better error checking for when ChiSquared does not match the text thats provided.

[CameronLonsdale]

The problem is that the - is not ascii so the blacklist of characters to ignore didnt pick it up and the shift moved along when it shouldn't. We should swap this to be a whitelist (using characters from the ChiSquared) Which mean, chisquared will have to become mandatory? Or somehow defining the whitelist of characters...