update epub template

add buildElement inline method
if paragraph is None: return page break
if paragraph is list or tuple: return <p> list
if paragraph is dict: return <d['tag'] **d>d['text']</d['tag']>
if paragraph is str, unicode or other type: return <p>str</p>

Signed-off-by: Young-Ho Cha <ganadist@gmail.com>
add bootstrap and jquery

Signed-off-by: Young-Ho Cha <ganadist@gmail.com>
can add external js resource

Signed-off-by: Young-Ho Cha <ganadist@gmail.com>
apply bootstrap in templates

Signed-off-by: Young-Ho Cha <ganadist@gmail.com>
apply bootstrap style for butterfly

Signed-off-by: Young-Ho Cha <ganadist@gmail.com>