In the same time, it is useless to define to logformat when only
one is used. Using format closer to default apache allows to
more easily use various log parsers

For performance analysis, it is mandatory to keep logs for a very long
time. Also it is sometimes required to analyse a bug that happened
more than one more ago, so we have no other choices than keep logs
and not remove them.

Conflicts:
	software/kvm/software.cfg
	stack/kvm.cfg

PHP : Disable Strict mode reporting, Enable libxml in php. Warning : if libz*-dev is installed, php won't compile

As slapos.libnetworkcache does not depend on M2Crypto anymore, but on
existence of openssl in PATH drop building of this library and just
tweak slapgrid-sr environment to allow find the openssl in PATH.