The Makefile shouldn't call 'configure'

The build 'standard' is that the caller should run
  ./configure
  make

Signed-off-by: David Scott <dave.scott@citrix.com>
configure: add '--disable-tests' option

Unfortunately the unit tests don't work when run as unpriviledged
users inside unprepared chroots. This allows them to be skipped.

By default "./configure && make" will run the unit tests as before.

Signed-off-by: David Scott <dave.scott@citrix.com>
xapi.spec: run "configure"

Signed-off-by: David Scott <dave.scott@citrix.com>
xenserver build: run configure from mk/Makefile

Signed-off-by: David Scott <dave.scott@citrix.com>
Fix event.next after EVENTS_LOST

When recording the id of the latest dropped event, we need to sort the list of
ids as integers. Unfortunately in the forward port of the events.from patch from
clearwater-lcm-sp1 I accidentally sorted the list of ids as strings.

- : bool = false

- : bool = true

This corrupts the stored id, resulting in multiple EVENTS_LOST where only one
is expected.

Signed-off-by: David Scott <dave.scott@eu.citrix.com>
Merge pull request #1724 from djs55/fix-event.next

Fix event.next after EVENTS_LOST
Merge pull request #1721 from djs55/experiment

Increase mock-friendliness