Use .startswith and .endswith instead of [0] and [-1]

Because the case of an empty string then works.
Make quotify print useful error messages
Add relativize helper to rewrite URLs
Add paragraphize helper to add <p> where it's missing
Handle ; after ellipsis
Remove more img attributes
Add removeMeta helper function
Improve the "template" sanitize sequence
Alphabetize
Merge epubbase

Conflicts:
	sanitize.py