Analyzes the class for tag.
Resin performs optimizations in the java code it produces from a jsp
depending on the nature of the taglib's that are used. For example, if a
taglib class does not use doAfterBody() then Resin can optimize the code it
produces for the jsp that uses that tag.
In order to determine the nature of a certain tag, and thus the
optimizations that can be performed, Resin analyzes the tag's class.
It does this in two stages: first it uses reflection to look at the class
and then it uses bytecode analysis to look at the class.