fix (language) auto-detect and auto-load relevant language files during CMP initialization

[potench]

Fix

• auto-detect config.language and auto-load relevant language files during CMP initialization
• configurable config.theme.maxWidthModal

Test Plan

Automatic Detection

1. chrome://settings, search for "language", change your default language from "english" to "sweedish"
2. yarn dev
3. go to http://localhost:8080/tcf-2.0.html
4. See browser language reflected in CMP.

Force Language

1. change config.language to "it", reload, see CMP display in Italian

Fallback to en

1. change config.language to "test", reload, see CMP display in english.