Reduce intltool requirements to version 0.35 for compatibility with Centos 5

Use strings to identify section types in the on-disk repo format.

Previously, a given razor file type had a fixed number of sections in a
fixed order, identified by an integer type. Now, sections are identified
by a named string (stored in a string pool after the section lists).

This will allow for razor files to contain arbitrary sections.

For bonus points, also drop the 4k section alignment and change the
magic byte string to "RZDB".

committer: Kristian H?gsberg <krh@redhat.com>

Convert main.c to use razor_root for most cases.

With this we change the default repo location to /var/lib/razor, but let the env
variable RAZOR_ROOT override it.

Change the install iterator API to what we want.

Always open all three rzdb files when we're merging package sets.

Fix old typo in file merging code.

Use the file string pool when merging directories.

Rename a couple more .repo references.

Move DEPSOLVE.txt and REPO.txt into docbook.

A little messy, but it's a first step towards pulling all the docs into
a nice self-contained document.

rename the .repo files to .rzdb files