Fix alternation order of lexical rules #2126
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This fixes the order of PUNCTUATION given our interpretation of "first match wins" for alternation. This moves the longer strings to the start to prevent any prefix matching from happening (for example `.` instead of `...`).
This fixes the order of LIFETIME_TOKEN (and LIFETIME_OR_LABEL) given our interpretation of "first match wins" for alternation. This moves RAW_LIFETIME to the start, otherwise a raw lifetime `'r#foo` would be interpreted as LIFETIME_TOKEN (`'r`) PUNCTUATION (`#`) IDENTIFIER_OR_KEYWORD (`foo`).
This fixes the order of FLOAT_LITERAL given our interpretation of "first match wins" for alternation. This moves the first rule (which matches things like `3.`) to the end so that other two rules have a chance to match something. Otherwise, input like `3.14` would be FLOAT_LITERAL (3.) INTEGER_LITERAL (14).
This fixes the order of INTEGER_LITERAL given our interpretation of "first match wins" for alternation. This moves DEC_LITERAL to the end of the list. Otherwise, an input of `0b1` would be interpreted as INTEGER_LITERAL (0) IDENTIFIER_OR_KEYWORD (b) INTEGER_LITERAL (1) instead of INTEGER_LITERAL (0b1).
With our interpretation of "first match wins" with alternation, this fixes a problem where INTEGER_LITERAL was incorrectly in front of FLOAT_LITERAL. Otherwise, an input of `1.2` would be interpreted as `INTEGER_LITERAL`, `PUNCTUATION`, `INTEGER_LITERAL` instead of `FLOAT_LITERAL`.
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This fixes the order of several of the lexical rules given our interpretation of "first match wins" for alternation.