Adding template functions to generate JS and CSS tags

Adding assets_js, assets_css template functions

Adding Assets functions for the template, to generate HTML tags for JS and CSS

Improve unhandled error handling in prod mode

This reverts commit c2079276.

Improve unhandled error handling in prod mode

miswrite a type of word

Fixed some typos

beeapi example is broken

panic if parse failed

panic if parse config failed

remove duplicated config initialization

case insensitive for section and key for ini config

there is no need to check if b.params is nil

update logic for check ini comments

if iniconf.String("demo.key1") != "asta" {
+		t.Fatal("get demo.key1 error")
+	}
+	if iniconf.String("demo.key2") != "xie" {
+		t.Fatal("get demo.key2 error")
+	}