add Gemfile
let section support add_image function
let section add_image function support block
adjust add image block realize
update rubyzip to 1.0.0 later
support add different image file in odf file section
fix image path error
resolve add image file href invalid error
resolve ignore update content.xml file error
fix image spelled wrong error.
Merge branch 'master' of https://github.com/comme/odf-report

Conflicts:
	lib/odf-report/section.rb
	odf-report.gemspec
Merged comme's and eFusions forks to add remove section and add image to section functionality