deploy: Fix package installation process

When local packages are used (use_local_packages = True in
deploy.conf) we do:

 dpkg -i <local_package.deb> || apt-get install -f

The first command leaves a broken package while the latter fixes it.
For some reason this DOES upgrade the installed packages that the
broken one depends on. To bypass this strange behavior,
after dpkg -i we run apt-mark hold.

Additionally remove any dependencies in all components in order
to check if control files are generated properly. Leave only
python-svipc for ArchipSynnefo and memcached in Cyclades.

Install snf-image 0.14 that does still work with nfs and does not
require a rados backend.

Rename WEB to Webproject.

Signed-off-by: Dimitris Aragiorgis <dimara@grnet.gr>
deploy: Introduce unified parse() decorator

This is used by certain components to parse the output based on
given regular expression and updates the context attributes based
on the given keys.

Modify get_* methods to get one argument that denotes the identity
(mail, service, cluster) to search for.

Signed-off-by: Dimitris Aragiorgis <dimara@grnet.gr>
deploy: No need to run snf-image-update-helper

snf-image-update-helper runs during post-install phase of
the debian package. Remove it from initialize().

Signed-off-by: Dimitris Aragiorgis <dimara@grnet.gr>