xapi: Set OCAMLRUNPARAM to enable backtraces

Signed-off-by: Euan Harris <euan.harris@citrix.com>
Merge pull request #116 from euanh/openstack-fixes

xapi: Set OCAMLRUNPARAM to enable backtraces
Warn the user not to call their user "mock"

Added some text pointing at "mock" install instructions.

Using "<user>" "mock" gives a confusing error message:
```
[root@st30 ~]# useradd mock -G mock
useradd: group mock exists - if you want to add this user to that group, use -g.
```
Merge pull request #118 from euanh/build-improvements

configure: Initialize the repository in RPMS
specs: Change xen-org to xapi-project in URLs

Signed-off-by: Euan Harris <euan.harris@citrix.com>
readme: Fix quotes around <user> in setup instructions

Should be backticks, not double quotes
Merge pull request #119 from euanh/great-renaming

specs: Change xen-org to xapi-project in URLs
Merge pull request #120 from euanh/build-improvements

configure: Create RPMS if it doesn't exist
specs: Update to latest ocaml-qmp

Signed-off-by: Euan Harris <euan.harris@citrix.com>