clang-tidy; Allow single line stmts w/o braces.

.clang-tidy

@@ -5,3 +5,10 @@ WarningsAsErrors: ''
 HeaderFilterRegex: '.*'
 AnalyzeTemporaryDtors: false
 FormatStyle:     file
+CheckOptions:
+  - key:             google-readability-braces-around-statements.ShortStatementLines
+    value:           '1'
+  - key:             hicpp-braces-around-statements.ShortStatementLines
+    value:           '1'
+  - key:             readability-braces-around-statements.ShortStatementLines
+    value:           '1'