Add RuleSet

[ghost]

添加特性：RuleSet

• 支持多配置文件
• 支持与其他规则配合使用
• 支持套娃

定义一个RuleSet：

{
  "tag": "rs",
  "rules" : [
    {
      "type": "field",
      "ip": [
        "8.8.8.8"
      ]
    },
    {
      "type": "field",
      "domain": [
        "domain:google.com"
      ]
    }
  ]
}

在RuleObject或RuleSet使用RuleSet：

{
  "type": "field",
  "ruleSet": "rs",
  "outboundTag": "outbound"
}

[AkinoKaede]

应当保持命名风格一致，建议改成 ruleSet

[badO1a5A90]

虽然会让路由规则更显得复杂化，但表示支持的，加入ruleset可以方便写各种组合规则。

[AkinoKaede]

Xray-core/app/router/condition_test.go

Line 324 in 16544c1

cond, err := test.rule.BuildCondition()

Xray-core/app/router/config.go

Line 66 in 95e025c

func (rr *RoutingRule) BuildCondition(rsm *rsManager) (*ConditionChan, error) {

测试需要修下

[decorativefamily]

There are several old pr's that I think should be identified