fix: goctl genhandler duplicate rest/httpx & template import custom

[smithyj]

fix: goctl genhandler duplicate rest/httpx & goctl genhandler template support custom import httpx package

Reason:
1、在 handler 层，我对 httpx 包进行了再次封装
2、在某些情况下，我需要控制 httpx 包的导入
3、goctl 1.3.9 会出现两个 rest/httpx 包

Example:

# handler.tpl
package {{.PkgName}}

import (
	"net/http"

	"appservice/pkg/resultx"
	{{.ImportPackages}}
        {{if .HasRequest}}
	{{.ImportHttpxPackage}}
        {{end}}
)

func {{.HandlerName}}(svcCtx *svc.ServiceContext) http.HandlerFunc {
	return func(w http.ResponseWriter, r *http.Request) {
		{{if .HasRequest}}var req types.{{.RequestType}}
		if err := httpx.Parse(r, &req); err != nil {
			resultx.HttpParamErrorResult(r, w, err)
			return
		}

		{{end}}l := {{.LogicName}}.New{{.LogicType}}(r.Context(), svcCtx)
		{{if .HasResp}}resp, {{end}}err := l.{{.Call}}({{if .HasRequest}}&req{{end}})

		{{if .HasResp}}resultx.HttpResult(r, w, resp, err){{else}}resultx.HttpResult(r, w, nil, err){{end}}

	}
}

[smithyj]

@anqiansong

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@an Qian send

[smithyj]

@kevwan

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@kevwan

[kesonan]

LGTM

[jsonMark]

这个情况我也遇到了。我们是同微信交互。

[Issues-translate-bot]

Bot detected the issue body's language is not English, translate it automatically. 👯👭🏻🧑‍🤝‍🧑👫🧑🏿‍🤝‍🧑🏻👩🏾‍🤝‍👨🏿👬🏿

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I also encountered this situation. We are interacting with WeChat.