feat(strct-tags): add support for tag options (#126)

* feat(struct_tags): add options support

* refactor(struct-tags): give input field better name

* feat(struct-tag): add default option

* refactor: make it work on neovim version below 0.12

* chore(struct-tags): update the demo

* refactor: unite struct_tags util with main logic

spec/fixtures/tags/overwrite_default_option_input.go

@@ -0,0 +1,8 @@
+package main
+
+type Test struct {
+	ID      int
+	Another struct {
+		Second string
+	}
+}

spec/fixtures/tags/overwrite_default_option_output.go

@@ -0,0 +1,8 @@
+package main
+
+type Test struct {
+	ID      int `xml:"id,otheroption"`
+	Another struct {
+		Second string `xml:"second,otheroption"`
+	} `xml:"another,otheroption"`
+}

spec/fixtures/tags/remove_with_option_input.go

@@ -0,0 +1,11 @@
+package main
+
+type Test struct {
+	ID      int    `json:"id,omitempty" xml:"id,someoption"`
+	Name    string `json:"name,omitempty" xml:"name,someoption"`
+	Num     int64  `json:"num,omitempty" xml:"num,someoption"`
+	Another struct {
+		First  int    `json:"first,omitempty" xml:"first,someoption"`
+		Second string `json:"second,omitempty" xml:"second,someoption"`
+	} `json:"another,omitempty" xml:"another,someoption"`
+}

spec/fixtures/tags/remove_with_option_output.go

@@ -0,0 +1,11 @@
+package main
+
+type Test struct {
+	ID      int    `xml:"id,someoption"`
+	Name    string `xml:"name,someoption"`
+	Num     int64  `xml:"num,someoption"`
+	Another struct {
+		First  int    `xml:"first,someoption"`
+		Second string `xml:"second,someoption"`
+	} `xml:"another,someoption"`
+}

spec/fixtures/tags/with_default_option_input.go

@@ -0,0 +1,8 @@
+package main
+
+type Test struct {
+	ID      int
+	Another struct {
+		Second string
+	}
+}

spec/fixtures/tags/with_default_option_output.go

@@ -0,0 +1,8 @@
+package main
+
+type Test struct {
+	ID      int `xml:"id,theoption"`
+	Another struct {
+		Second string `xml:"second,theoption"`
+	} `xml:"another,theoption"`
+}

spec/fixtures/tags/with_option_input.go

@@ -0,0 +1,11 @@
+package main
+
+type Test struct {
+	ID      int
+	Name    string
+	Num     int64
+	Another struct {
+		First  int
+		Second string
+	}
+}

spec/fixtures/tags/with_option_output.go

@@ -0,0 +1,11 @@
+package main
+
+type Test struct {
+	ID      int    `json:"id,omitempty"`
+	Name    string `json:"name,omitempty"`
+	Num     int64  `json:"num,omitempty"`
+	Another struct {
+		First  int    `json:"first,omitempty"`
+		Second string `json:"second,omitempty"`
+	} `json:"another,omitempty"`
+}