Enhancement of IL Pattern

* Metadata: Improve the equality detection of Types and Methods.
* Metadata: Move hash computing and equality comparison processes which were defined as free functions to each member. Because xxMetadata-side and xxGenerator-side were indistinguishable.
* Metadata: Now support the metadata investigation of generic method.
* Metadata: Remove unnecessary logs.
* Metadata: [BUG FIX] Corrected the parsing process for generic type instance.