drop QA notice for use flags missing from IUSE for < EAPI-5

The specification isn't complete in the description of what is required
for EAPIs < 5 in IUSE_EFFECTIVE. Specifically portage adds more values
including those from masking and forcing related profile files and the
build and bootstrap flags used by catalyst.
minor bash style consistency and indentation fixes
minor indentation and alignment fixes
don't check if the selinux use flag is enabled, only check FEATURES

Checking for a nonexistent use flag errors out for >= EAPI-5 as required
by the spec that forces verification of use flag queries against values
in IUSE_EFFECTIVE.
minor spelling, indentation, and whitespace fixes
use utf8 encoding to read ebuild files for parsing EAPI

This fixes decode errors found when using python-3 since ebuilds can
have unicode characters in them.