Description of problem:
oVirt fails to load the list of VMs when querying a VMware vCenter that includes few special chars within the VMware-datacenter or VMware-cluster.
The same reproduced when running virsh ot virt-v2v.

Details:
The ovirt engine sends the already encoded uri to VDSM (a fix for Bug 1356767), 
But it fails on libvirt or virtv2v with two kind of errors:
1. For any one of the following chars exists in datacenter/cluster: %, /, \ 
the following error appears in libvirt:
"Could not find datacenter specified in <uri>"

2. For any one of the following chars exists in datacenter/cluster: &, +, =, ?
the following error appears in virt-v2v:
virt-v2v: error: internal error: invalid argument: cannot fetch XML
description of guest '111': internal error: HTTP response code 404 for
download from
'https://vcenter:443/folder/111%2f111%2evmx?dcPath=Folder1%2fFolder2%2fCompute%2b3&dsName=global'

or from vdsm log:
jsonrpc.Executor/6::ERROR::2016-08-31 14:20:10,003::v2v::168::root::(get_external_vms) error getting domain xml for vm 'RHEL7_thick_eager_zeroed': internal error: HTTP response code 404 for download from 'https://vcenter:443/folder/RHEL7%5fthick%5feager%5fzeroed%2fRHEL7%5fthick%5feager%5fzeroed%2evmx?dcPath=Folder1%2fFolder2%2fCompute%2b1&dsName=nsimsolo%5fiSCSI%5f3'


Version-Release number of selected component (if applicable):
libvirt Version     : 1.2.18.4
ovirt 4.0.4

How reproducible:
100%

Steps to Reproduce:
1. Declare a VMware data center or cluster with one of the chars described above.
2. a. Try to run virsh -c "vpx://administrator@vcenter/encoded-datacenter/encoded-cluster/esxi?no_verify=1" with the datacenter,cluster declared in 1.

b. or if (a) passes, try to run:
virt-v2v -v -x -o null -ic "vpx://administrator@vcenter/encoded-data-center/encoded-cluster/esxi?no_verify=1"  vm-to-import

Actual results:
a. the following error appears:
error: failed to connect to the hypervisor
error: internal error: Could not find datacenter specified in '/datacenter/cluster/esxi'

b. The following error appears:
virt-v2v: error: internal error: invalid argument: cannot fetch XML
description of guest 'vm-to-import': internal error: HTTP response code 404 for
download from
'https://vcenter:443/encoded-datacenter/encoded-cluster&dsName=global'

Expected results:
it should work without errors as done with other special chars.

Additional info: