speed optimizations
add content_model to block, rename buffer to lines
convert more ERB templates to string templates
convert more ERB templates to string templates
super single or multiple terms on labeled list
resolves #486 add docinfo option for footer
Merge pull request #553 from mojavelinux/docinfo-footer

resolves #486 add docinfo option for footer
optimizations and cleanups

- use constant for endline
- use string template for dlist
- store toc lines in array, then join
- add test for strong option on horizontal list
- join rendered blocks on endline
additional HTML5 template cleanups
extract method for parsing manpage header
resolves #411 add DocBook 5 backend
add xmlns to root element in docbook45 backend
noxmlns attribute disables xmlns in DocBook 4.5
Merge pull request #544 from mojavelinux/docbook5

resolves #411 add DocBook 5 backend
resolves #556 print warning/error messages using warn
Merge pull request #558 from mojavelinux/print-messages-with-warn

resolves #556 print warning/error messages using warn
rework Block constructor, optimizations

- use options array to pass Block properties to constructor
- use left shift operator to add blocks to parent
- allow paragraph text to be passed to Block as string
- pull content_model up to AbstractBlock
- add :empty content_model
- pull up some regexps to constants
- update rdoc
cleanups and optimizations

- only normalize option attributes for top-level document
- only set dynamic attributes on top-level document
- set dynamic attributes before loading reader
- optimize several non-nil checks
add get_lines and terminate methods to Reader
resolves #523 set defaults for attribute-missing & attribute-undefined