Rdoc detection regexp highly deficient

[zenspider]

The rdoc detection regexp is, well... it's not good:

1. Requires an H2+ tag. What if I don't want sections in my description?
2. Requires it to start with capital A-Z. ASCII? What if I want my description to be in Japanese?
3. ... that's it? a header? What about ANY of the other markup that rdoc provides?

Minitest's readme has plenty of rdoc markup but because I don't have an H2 in the gem's description, it renders as an ugly unreadable blob of text.