LICENSE: make it clear it's a MIT license
Translated to english and converted to Markdown
util: Rename gen-svn-config to gen-beta-config
Replace SVN with Beta

We're not in SVN anymore.
Git is the king, for now.
Beta is a future-proof term.
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Workaround lacking of SVN automatic revision number

In SVN one could use `$Revision$` to automatically expand to the
current revision number. Git doesn't have an equivalent for that, so we
must remove this feature.

Now the Cloud version will be the latest Git hash and will link to the
current commit (since it is generated, it's possible).

The Beta version will be infinite ∞ and will link to the repository
root.

Browser and Portable versions will continue to link to the current
version News page.
Use β instead b to identify beta version
New flag isBeta

For future features
About: show current year when in β
About: show commit hash when in β

In all flavors, except 'txt' mode where we can't get the current hash.