refactor(uncrustify): change rules to better align with the style guide

Add space around arithmetic operators '+' and '-'.
Remove space between back-to-back parentheses, i.e. ')(' vs. ') ('.
Remove space between '((' or '))' of control statements.
Add space between ')' and '{' of control statements.
Remove space between function name and '(' on function declaration.
Collapse empty blocks between '{' and '}'.
Remove newline at the end of the file.
Remove newline between 'enum' and '{'.
Remove newline between '}' and ')' in a function invocation.
Remove newline between '}' and 'while' of 'do' statement.

src/nvim/diff.c

@@ -2558,8 +2558,7 @@ void ex_diffgetput(exarg_T *eap)
       p--;
     }
 
-    for (i = 0; ascii_isdigit(eap->arg[i]) && eap->arg + i < p; i++) {
-    }
+    for (i = 0; ascii_isdigit(eap->arg[i]) && eap->arg + i < p; i++) {}
 
     if (eap->arg + i == p) {
       // digits only