feature #3180: options for SSL certs in OCA

ONE_CERT_DIR: adds an extra directory with trusted CA certificates
ONE_DISABLE_SSL_VERIFY: disable certificate verification

Both of these options make the calls change from asynchronous (one http
connection per call) to synchronous (same http connection for all calls).
XMLRPC library creates a new HTTP object per asynchronous connection and
there is no way of passing configuration options to it.
feature #3180: add option to make xmlrpc calls synchronous

Using SSL options in Ruby OCA no longer disable async calls automatically. The sync call
must be specified when creating a client:

client = OpenNebula::Client.new(secret, proxy, :sync => true)
feature #3180: make CLI use sync calls to honor SSL parameters
bug #3216: xen4 reset executes reboot with ACPI

xen 4.2 lacks reset command and can not be implemented with the information provided to
the driver (lacks deployment file path). The driver is changed so it calls reboot with
-F parameters so it will send ACPI signal in case it is HVM and does not have PV drivers.
feature #3174: Display resource name in header-resource
Bug #3163: ARP cache poisoning does not work with L2 networks
Merge remote-tracking branch 'origin/bug-3216'
feature #3180: Raise an exception for not compatible client options
Merge branch 'feature-3180'
bug #3262: Hosts in init/error state has no hypervisor defined
Add support for proxy certificates to X509 Cloud Auth
Hide password arguments for user login. General hidden process
change scope of log method
Custom format string to log xml-rpc calls
Update translations
Substitute c12g.com for opennebula.systems
Bump version to 4.10.0
Bump man pages
Feature #3243: Remove openSUSE from install_gems as it's no longer an official platform of OpenNebula
Bug #3258: Add mysql gem to Centos distros