enh(C): Add linter to check for warnings

Author: davidhcefx

c.nanorc

@@ -2,7 +2,9 @@
 ##
 syntax "C" "\.(c(c|pp|xx)?|C)$" "\.(h(h|pp|xx)?|H)$" "\.ii?$" "\.(def)$" "\.ino$"
 magic "^(C|C\+\+) (source|program)"
+linter "g++ -fshow-column -Wall"
 comment "//"
+
 color brightred "\<[A-Z_][0-9A-Z_]+\>"
 color green "\<(float|double|bool|char|wchar_t|int|short|long|sizeof|enum|void|static|const|struct|union|typedef|extern|(un)?signed|inline)\>"
 color green "\<((s?size)|(char(16|32))|((u_?)?int(_fast|_least)?(8|16|32|64))|u?int(max|ptr))_t\>"