[broken] Ignore lifetime and params with #[zerogc(ignore)] attribute

This is broken because we can't have helper-attributes on lifetimes and
parameters in the current rust nightly :(

This replaces the #[zerogc(ignore_params(A, B, C))] setting
See issue #17

Author: Techcable

libs/derive/Cargo.toml

@@ -15,6 +15,7 @@ proc-macro = true
 zerogc = { version = "0.1.3", path = "../.." }
 
 [dependencies]
+indexmap = "1"
 # Proc macros
 syn = "1.0.55"
 quote = "1.0.8"