adding Eclipse project files and completing the module dependencies
fixing Puppet style issues
("->', http://docs.puppetlabs.com/guides/style_guide.html#quoting and class name).
replacing emirepos::emi2repositories with full repo definitions
for now (emirepos not available outside cernops)
removing AFS dependency as it is not supported on most sites
and not a dependency of glexec_wn
fixing error due to missing $supported_vos parameter
(and not inheriting from glexecwn::params either)
These are several commits in one:
1) Add parameters to the necessary modules to make clear what is used in the sames.
   Now the module can be used with Foreman and scripts (as well as hiera)
2) Changing the structure slightly:
    a) removing site-env.pp (merged with env.pp) as they have same parameters
    b) adding config.pp and moving configuration (including dependencies) in there
3) Adding 'Scientific' to supported OS (the fact defaults to that on SL 6.4)
4) making dummydpm and vosupport (see cernops/puppet-vosupport/#1) optional
5) changing exec to change file permissions to file class (otherwise it runs every time!)
Making emi_wn optional and params beatiful:
a) making emi_wn an optional package as it tries
to import 32 bit packages (replacing 64 bit ones)
on our HTCondor WNs
see fix:
https://www.jiscmail.ac.uk/cgi-bin/webadmin?A2=LCG-ROLLOUT;9c44abbe.1310

b) formatting params and ordering alphabetically
making the glexec binary permissions a parameter