Namespace separation

[samchon]

Separated some functions under json and misc for protobuf.

When protobuf features come into typia, name of JSON related functions would be similar with protobuf. Also, when more features like cbor, messagePack and gql come, naming global functions of the root scope would be much different. typia is not a library for only runtime validation and JSON serialization more.

Therefore, decided to separate namespaces like below.

```typescript
// RUNTIME VALIDATORS
export function is<T>(input: unknown): input is T; // returns boolean
export function assert<T>(input: unknown): T; // throws TypeGuardError
export function validate<T>(input: unknown): IValidation<T>; // detailed
export const customValidators: CustomValidatorMap; // for customization

// JSON FUNCTIONS
export namespace json {
    export function application<T>(): IJsonApplication; // JSON schema
    export function assertParse<T>(input: string): T; // type safe parser
    export function assertStringify<T>(input: T): string; // safe and faster
}

// PROTOCOL BUFFER
export namespace protobuf {
    export function message<T>(): string; // Protocol Buffer message
    export function assertDecode<T>(buffer: Buffer): T; // safe decoder
    export function assertEncode<T>(input: T): Uint8Array; // safe encoder
}

// RANDOM GENERATOR
export function random<T>(g?: Partial<IRandomGenerator>): T;