Standard error reporting functionality.
Refactoring error handling.
Refactoring error handling.
Allow "terminate" value to be passed to log-message template as a parameter.
Handling for "DEBUG" level messages.
Refactored log/error handling for EPUB stylesheets.
Log/error handling refactoring for labeling.
Log/error handling refactoring for xrefgen.
Merge pull request #77 from oreillymedia/htmlbook-xsl

Standardized error handling