Use glamour and termev to render/colorize content (#181)

Merge branch 'master' into use-glamour

select Glamour Theme based on BackgroundColor

Merge branch 'master' into use-glamour

Merge branch 'master' into use-glamour

update termev

update go.mod

label color colorate

use glamour for issue content

Vendor: Add glamour

Co-authored-by: Lunny Xiao <xiaolunwen@gmail.com>
Co-authored-by: 6543 <6543@obermui.de>
Reviewed-on: https://gitea.com/gitea/tea/pulls/181
Reviewed-by: techknowlogick <techknowlogick@gitea.io>
Reviewed-by: Lunny Xiao <xiaolunwen@gmail.com>

vendor/github.com/alecthomas/chroma/styles/api.go

@@ -0,0 +1,37 @@
+package styles
+
+import (
+	"sort"
+
+	"github.com/alecthomas/chroma"
+)
+
+// Registry of Styles.
+var Registry = map[string]*chroma.Style{}
+
+// Fallback style. Reassign to change the default fallback style.
+var Fallback = SwapOff
+
+// Register a chroma.Style.
+func Register(style *chroma.Style) *chroma.Style {
+	Registry[style.Name] = style
+	return style
+}
+
+// Names of all available styles.
+func Names() []string {
+	out := []string{}
+	for name := range Registry {
+		out = append(out, name)
+	}
+	sort.Strings(out)
+	return out
+}
+
+// Get named style, or Fallback.
+func Get(name string) *chroma.Style {
+	if style, ok := Registry[name]; ok {
+		return style
+	}
+	return Fallback
+}