Generic/CamelCapsFunctionName: improve inline documentation

* This sniff only listens to `T_FUNCTION`. It does not listen to
    `T_FN` or `T_CLOSURE`. So the inline code comments were incorrect. The if
    conditions are still valid to bail early when live coding, but they do not
    ever apply to closures or arrow functions (anymore - it was possible in the past though).
* The inline comments regarding leading underscores was inaccurate as the code
    removes all leading underscores, not just the first.

Author: rodrigoprimo

src/Standards/Generic/Sniffs/NamingConventions/CamelCapsFunctionNameSniff.php

@@ -113,7 +113,7 @@ protected function processTokenWithinScope(File $phpcsFile, $stackPtr, $currScop
 
         $methodName = $phpcsFile->getDeclarationName($stackPtr);
         if ($methodName === null) {
-            // Ignore closures.
+            // Live coding or parse error. Bow out.
             return;
         }
 
@@ -150,7 +150,7 @@ protected function processTokenWithinScope(File $phpcsFile, $stackPtr, $currScop
             return;
         }
 
-        // Ignore first underscore in methods prefixed with "_".
+        // Ignore leading underscores in the method name.
         $methodName = ltrim($methodName, '_');
 
         $methodProps = $phpcsFile->getMethodProperties($stackPtr);
@@ -189,7 +189,7 @@ protected function processTokenOutsideScope(File $phpcsFile, $stackPtr)
     {
         $functionName = $phpcsFile->getDeclarationName($stackPtr);
         if ($functionName === null) {
-            // Ignore closures.
+            // Live coding or parse error. Bow out.
             return;
         }
 
@@ -206,7 +206,7 @@ protected function processTokenOutsideScope(File $phpcsFile, $stackPtr)
             $phpcsFile->addError($error, $stackPtr, 'FunctionDoubleUnderscore', $errorData);
         }
 
-        // Ignore first underscore in functions prefixed with "_".
+        // Ignore leading underscores in the method name.
         $functionName = ltrim($functionName, '_');
 
         if (Common::isCamelCaps($functionName, false, true, $this->strict) === false) {