Documentation for .travis.yml is too ambiguous

[scfc]

I'm trying to debug Travis CI failures for https://github.com/ejmr/php-mode. Its .travis.yml refers to https://raw.github.com/rejeep/evm/master/go, while this repository's README.md (also) refers to https://gist.github.com/rejeep/ebcd57c3af83b049833b. README.md cryptically says "sudo is not possible" (which I believe Travis CI still allows to be used) and that -bin versions will be removed and -travis should be used instead.

If I try and err, I can "achieve" errors like for example (https://travis-ci.org/scfc/php-mode/jobs/272320178):

$ emacs -Q --batch --eval '(message (emacs-version))'
Warning: arch-dependent data dir (/tmp/emacs-24.3-travis/libexec/emacs/24.3/x86_64-unknown-linux-gnu/) does not exist.
Warning: arch-independent data dir (/tmp/emacs-24.3-travis/share/emacs/24.3/etc/) does not exist.
Warning: Lisp directory `/tmp/emacs-24.3-travis/share/emacs/24.3/lisp' does not exist.
Warning: Lisp directory `/tmp/emacs-24.3-travis/share/emacs/24.3/leim' does not exist.
Error: charsets directory not found:
/tmp/emacs-24.3-travis/share/emacs/24.3/etc/charsets
Emacs will not function correctly without the character map files.
Please check your installation!

Before I delve into this any further, I'd like to have some foundation to build upon: What .travis.yml configuration(s) should work, with sudo: required and without? How should Emacs be installed and used? Etc. IMHO the current documentation is too ambiguous in that regard.