Reverts commits cef44e1 and 548f4e3.

Commit 15a631c introduced an undefined function warning.

When the new string module is merged to master, this commit can be
reverted.

Commit 15a631c introduced a Dialyzer warning.

When the new string module is merged to master, this commit can be
reverted.

Also extended the scanner to handle the \x{...} syntax.

Capitalizing now works with a few more characters.

This makes it clear that Apache 2.0 applies, without dropping the old LGPL
licensing, and makes all the EDoc file headers look the same as upstream.