Parsing fails on nested tags

[deveiant]

[From an email from <rh{at}roberthahn{dot}ca>]:

While working on a project that utilizes BlueCloth, I found an interesting bug that causes the parser to break badly.

If I wanted to print out some HTML with an SSI in it, like this:

     <a href="<!--#echo var="PAGE"-->"> ...</a>

The parser dies because it doesn't expect a nested tag.

[deveiant]

Oops. Removed email encoding stuff from the testcase.

[deveiant]

Fixed exposed email address.

[roberthahn]

This file, found in BlueCloth/tests/, has been augmented to add a new test case (1/2)

[roberthahn]

This file, found in BlueCloth/tests/data, has been created to illustrate possible error scenarios (2/2)

[roberthahn]

Added test case and representative data file to assist with coding a fix.