𝛼 break CMU braile option

[pablgonz]

When checking this with any language setting in MathCAT-demo and setting Braille to CMU:

<math xmlns="http://www.w3.org/1998/Math/MathML">
 <mi intent="_ángulo" mathvariant="normal">∠</mi>
 <mi>𝛼</mi>
</math>

The result is:

Pattern match/replacement failure! caused by: attempting replacement pattern: "default" for "math". Replacement ["*"] ...due to matching the MathML
∠ 𝛼
with the pattern "." The patterns are in Rules/Braille/CMU/CMU_Rules.yaml. caused by: attempting replacement pattern: "default" for "mrow". Replacement ["*"] ...due to matching the MathML ∠ 𝛼 with the pattern "." The patterns are in Rules/Braille/CMU/CMU_Rules.yaml. caused by: attempting replacement pattern: "default" for "mi". Replacement - "BrailleChars(., 'CMU')" - test: [ if: '"string-length(.) > 1 and translate(., 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ', '') = '' and not(@class='MathML-unit' or contains(@intent, ':unit') )"' then:[t: "."]] ...due to matching the MathML 𝛼 with the pattern "." The patterns are in Rules/Braille/CMU/CMU_Rules.yaml. caused by: in 'BrailleChars(., 'CMU')' replacing after pattern match caused by: error while evaluating function: could not evaluate function: Unicode replacement error: spell: "translate('𝛼', '𝛼𝛽𝛾𝛿𝜀𝜁𝜂𝜃𝜄𝜅𝜆𝜇𝜈𝜉𝜊𝜋𝜌𝜍𝜎𝜏𝜐𝜑𝜒𝜓', '𝛼𝛽𝛾𝛿𝜀𝜁𝜂𝜃𝜄𝜅𝜆𝜇𝜈𝜉𝜊𝜋𝜌𝜍𝜎𝜏𝜐𝜑𝜒𝜓')" 

[moritz-gross]

Problem seems to be in Rules/Braille/CMU/unicode-full.yaml.

Here, italic characters get re-mapped back to themselves, leading to infinite recursion, blocked by MAX_TRANSLATE_RECURSION:

- "𝛼-𝜓": 
  - tc: "GL" 
  - spell: "translate('.', '𝛼𝛽...', '𝛼𝛽...')"

@NSoiffer How is styling supposed to be handled? Should it just be discarded?

Aditionally, the range ends with Psi, but UEB goes up to Omega. Is that another bug?