tools: fix some typos

Created by: ghost

1. '256 color' should be '256-color'.
2. Replace all the non-English characters to English ones (such as “=>",”=>",‘=>',’=>') in the comments.

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• make -j4 test (UNIX), or vcbuild test (Windows) passes
• tests and/or benchmarks are included
• documentation is changed or added
• commit message follows commit guidelines