httpcaddyfile: Fix nested blocks; add handle directive; refactor

The fix that was initially put forth in #2971 was good, but only for
up to one layer of nesting. The real problem was that we forgot to
increment nesting when already inside a block if we saw another open
curly brace that opens another block (dispenser.go L157-158).

The new 'handle' directive allows HTTP Caddyfiles to be designed more
like nginx location blocks if the user prefers. Inside a handle block,
directives are still ordered just like they are outside of them, but
handler blocks at a given level of nesting are mutually exclusive.

This work benefitted from some refactoring and cleanup.

1 files changed, 1 insertions, 1 deletions

diff --git a/modules/caddyhttp/rewrite/rewrite.go b/modules/caddyhttp/rewrite/rewrite.go
index e2d57c44d..ad054866a 100644
--- a/modules/caddyhttp/rewrite/rewrite.go
+++ b/modules/caddyhttp/rewrite/rewrite.go
@@ -50,7 +50,7 @@ type Rewrite struct {
 	// You can also use placeholders. For example, to preserve the existing
 	// query string, you might use: "?{http.request.uri.query}&a=b". Any
 	// key-value pairs you add to the query string will not overwrite
-	// existing values.
+	// existing values (individual pairs are append-only).
 	//
 	// To clear the query string, explicitly set an empty one: "?"
 	URI string `json:"uri,omitempty"`