fix(caddyfile): bump expansion limits (#9)

A single maxSnippetExpansions of 1000 could be too low for some real
world scenarios. Snippet-based configuration can be used broadly
across large CoreDNS Corefiles. We cannot implement a pure
“import depth” integer with the current splice-then-continue parser
because imports are expanded by lexing and splicing tokens into the
stream, not by recursive function calls.

Instead, we introduce high default per-directive caps for snippet and
file imports, keeping globs counted as one. Prevent trivial snippet
self-import. Add tests that lower caps to validate failure on
cycles and success with large glob imports.

This should present a good enough middleground, instead of rewriting
the parser.

Signed-off-by: Ville Vesilehto <[email protected]>

fix(caddyfile): guard snippet import cycles (#8)

init plugins only for first zone in block (#1)

Signed-off-by: Chris O'Haver <[email protected]>

Rename the imports

Signed-off-by: Miek Gieben <[email protected]>