fix anythingButRange range parameters type

[carafelix]

changed anythingButRange parameters to string following the .range parameters

• The function checks for characters, not the charcodes, so the appropriate type is string, same as in the .range method. Check the issue bellow for examples.
• [ x ] Is there a related issue?
  • Type annotations for .anythingButRange mistakenly marked as number #75
• [ x ] Does the code style reasonably match the existing code?
• [ x ] Are the changes tested (using the existing format, as far as is possible?)
• [ x ] Is the index.d.ts file updated, using appropriate types and using the same description as the readme?

[francisrstokes]

Thanks for taking time out of your busy schedule investigating Sumerian mind-viruses to fix this 😄

Closes #75