This patch makes the Types module a base module, and Node/Instance ones
import it, from the previous (opposite) situation. This will allow in
the future to use newtypes for the index and name types.

This removes the return of ktn/kti from Loader.mergeData and associated
functions.

This patch removes all uses of ktn/kti from the past-loader stages.

Since we have Node/Instance.name, we can now simplify a few constructs.

This patch moves the common loading sequence to CLI, such that hbal/hn1
and possible future scripts that take the input from same sources can
use it.

This moves the remaining loading function to Loader (together with its
associated support functions).

This patch generalizes a little the CLI handling by not passing in a
special function for help and such, but instead requiring that the
options object supports some common functionality.

This new big patch does a couple of more cleanups in the loading of data
chapter:
  - introduce a Types module that holds most types (except the base
    Node/Instance/etc.) so that multiple other modules can use these
    (instead of only Cluster and its users)
  - bring IAlloc.hs in line with the recent changes of providing data
    types and not strings
  - removal of obsolete Utils.hs json-related functions

This big patch changes the loader model from “string data as common
format” to actual object structures as common format.

The text loading function move from Cluster.hs to a new Text.hs module,
some common functions are moved to a new Loader.hs module, and the
return values from both Rapi.hs and Text.hs are uniformized.

This patch changes Cluster.loadData to return a Result, instead of
directly the values; this will allow us to return meaningful error
values (e.g. when an instances lives on unknown node) rather than simply
abort. Currently the result is always an Ok, the actual signalling of
errors will come later.

Its callers are changed to accommodate for the new return type and to
display errors as needed.

This big patch converts from our home-grown monad-like constructs
(the Either stuff) to a real, Either-like-but-another-name monad.

We introduce a “Result a” monad, and this allows dropping many of the
extra constructs. Hopefully the code is also more clear.

Many of the functions could now be written in a generic-monad style,
instead of Result specifically, but that will come in future patches.

IAlloc.hs also has some unrelated patches.

This patch adds support for selecting the instance/node file names via
two environment variables (HTOOLS_NODES, HTOOLS_INSTANCES).

Unfortunately we still have lots of duplicated code, since the options
are not unified.

Neither hbal nor hn1 take any arguments beside the options, so if any
are passed is most likely an unintended error. This patch aborts in such
cases.

This patch adds checking of cluster data in the binaries and display of
node's x_mem/i_mem in the node list.

This patch moves the common CLI functionality (as much as currently
possible) into a separate module. This means we only have one parseOpts
and that Utils.hs doesn't keep this kind of functions anymore.

The modules are moved from the ‘top’ namespace to ‘Ganeti.HTools’, in
compliance with standard practices.

This patch moves the version string creation into a function in Utils
which shows some more information.

This patch adds a -V, --version command line option that shows the
program version and also updates the hn1 usage string (similar to hbal).

This patch moves the formatting of the command list to Cluster.hs and
enhances it with separator messages between the steps.

This patch adds printing the initial and final cluster coefficients in
hn1 too, to better understand the found solution.

This patch automatically removes the longest common (domain, i.e.
starting with a dot) suffix from the node and instance names. This gives
a much clearer display, and this format is compatible with the way
Ganeti accepts shortened names.

This patch moves a function to Utils and changes hn1 to be able to take
data from RAPI.

This is the initial import of release 0.0.3.