add charset detection and override option for html / htm / css / ...

[SylRob]

• add --charset option:String in config
• in startEndpoint before handler function check file extension
• if html | htm | css,
• if config.charset is set, force every request header Content-type to config.charset content
• else load the requested file in scanContentTypeCharset and scroll its content to find <meta ... charset="... or @charset "...
• if found, set the header Content-Type
• if not set utf-8 default header

the rest is handle bye serve-handeler

Can / should be extended to other extention (json, xml, etc... ?)

[alissonpelizaro]

Nothing wrong

[leerob]

We are rewriting the project in TypeScript - if you are still interested in contributing, could you open a PR against this branch? #706

Thank you!