Merge branch 'upstream_master'

README.md

@@ -78,8 +78,3 @@ List of Supported G-Codes in Grbl v1.1:
   - Spindle Control: M3, M4, M5
   - Valid Non-Command Words: F, I, J, K, L, N, P, R, S, T, X, Y, Z
 ```
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