v1.24.7

Viewer: add $$ syntax for inline formula

Since the version 1.19.8 Tp-Note can render mathematical formula. So far
inline formula had to be enclosed between `$ and $`. e.g. `$\alpha$`.
This former syntax, is still supported, is now deprecated.
The present release adds support for the standard syntax with simple $
enclosure, e.g. $\alpha$.

The former syntax for display formula:

```math
\alpha
```

can now be written as:

$$
\alpha
$$