Allow use of leading asterisk in rst blocks

Comment styles in doxygen that use a leading asterisk, such as

/*! 
 * Commenting
 * a bit
 */

cause the leading asterisk to be passed in to the verbatim block and pollute the desired rst.  This patch strips such leading asterisks in response to a embed:rat:leading-asterisk tag
Added example of usage of embed:rst:leading-asterisk tag
Tweak the asterisk handling logic and docs

We change the documentation to output a representation of the bad data
rather than feeding it the bad data and letting it give us a warning as
we're keen to keep warnings to a minimum.

The test case in the documentation was failing as the first character of
the line wasn't "*" so we tweak the logic to replace the first occurance
of * instead of assuming it is the first character.
Updated README to acknowledge donkopotamus

Thank you for contribution handling asterisks in the embedded rst
comments.
Synced the documentation credit list with the README acknowledgements
Merge branch 'donkopotamus-master'