trurl: run --trim query before --append query

Before this patch there was not a way to add a query parameter to a URL,
removing the previous value if the parameter was already present in the
base URL.

I tried to use:

  x () {
    trurl --verify --trim query=foo --append "query=foo=$2" -- "$1"
  }

But that didn't work since  --trim query  runs after --append query, so
the new value value added with --append also gets trimmed:

  $ x 'https://example.org/?foo=hello&baz=boo' 'howdy'
  https://example.org/?baz=boo

This patch make trurl run  --trim  before  --append  so that using
--trim query=foo --append query=foo=bar  works to set foo to bar
overwriting previous value of foo.

  $ x 'https://example.org/?foo=hello&baz=boo' 'howdy'
  https://example.org/?baz=boo&foo=howdy

I added a test for this, and I also added a test that tests that
--sort-query  and  --trim query  work together, since I noticed it was
missing.

tests.json

@@ -1981,5 +1981,38 @@
             "returncode": 0,
             "stderr": ""
         }
+    },
+    {
+        "input": {
+            "arguments": [
+                "-a",
+                "query=c=moo",
+                "--sort-query",
+                "https://example.org/foo?x=hi#rye"
+            ]
+        },
+        "expected": {
+            "stdout": "https://example.org/foo?c=moo&x=hi#rye\n",
+            "returncode": 0,
+            "stderr": ""
+        }
+    },
+    {
+        "input": {
+            "arguments": [
+                "--trim",
+                "query=a",
+                "-a",
+                "query=a=ciao",
+                "-a",
+                "query=b=salve",
+                "https://example.org/foo?a=hi&b=hello&x=y"
+            ]
+        },
+        "expected": {
+            "stdout": "https://example.org/foo?b=hello&x=y&a=ciao&b=salve\n",
+            "returncode": 0,
+            "stderr": ""
+        }
     }
 ]

trurl.c

@@ -1167,14 +1167,14 @@ static void singleurl(struct option *o,
 
     extractqpairs(uh, o);
 
+    /* trim parts */
+    trim(o);
+
     /* append query segments */
     for(p = o->append_query; p; p = p->next) {
       addqpair(p->data, strlen(p->data));
     }
 
-    /* trim parts */
-    trim(o);
-
     sortquery(o);
 
     /* put the query back */