Introduce .jenkins.sh
opam: add constraint: tyxml >= 3.1.0
Jenkins: install camlzip
Merge pull request #30 from ocsigen/jenkins

Jenkins now builds PR
Xhtml -> Html5
Merge pull request #31 from ocsigen/remove_xhtml

Xhtml -> Html5
Merge branch 'master' into 3.0.0-cohttp

Conflicts:
	src/http/ocsigen_senders.ml
Refactorize for locate casting between native and cohttp implementation (grep Of_cohttp|To_cohttp *.ml)