(maint) Disable warning register-deprecated.

This warning is specific to Clang, and marks register as deprecated.
Boost still uses register, and we're unlikely to (plus it doesn't
cause any harm when it's used), so the warning is now disabled.
Merge pull request #87 from MikaelSmith/maint/master/Disable-register-deprecated-warning

(maint) Disable warning register-deprecated.
(CFACT-44) Add missing Facter.version method.

Adding a missing Facter.version method that returns
Facter::FACTERVERSION.
(CFACT-44) Support boolean values in confines.

Support true and false in a Ruby confine hash.
(CFACT-44) Implement exec and which on Facter::Util::Resolution.

Implementing exec and which singleton methods on
Facter::Util::Resolution.

These call directly into the corresponding methods on Facter::Core::Execution.
(maint) Remove incorrect doc comment in #ifdef'd code.

Removing extraneous template argument doc comment.
(maint) Remove incorrect doxygen line
(doc) Remove duplicate info and add details.

OpenSSL was mentioned twice, so the entry under Visual Studio was fixed.
Some download instructions were also clarified.
Merge pull request #88 from MikaelSmith/doc/master/update-windows-instructions

(doc) Remove duplicate info and add details.
(maint) Clean removed package references.

Some references to RE2 and LOG4CXX were missed when removing the packages.
Remove those missed references.
Merge pull request #89 from MikaelSmith/maint/master/clean-removed-lib-refs

(maint) Clean removed package references.
Merge pull request #86 from peterhuene/custom/facts

(CFACT-44) More fixes for Ruby compatibility.
(CFACT-44) Bind to loaded Ruby (if present) instead of searching.

Currently we always search the file system for a Ruby library.
While we do check to see if the library found has already loaded,
if libfacter finds a different library than the already loaded Ruby
library, a separate VM will be created that will be isolated from
the original VM.  This would prevent facts from populating correctly.

POSIX libdl (and Windows through a different mechanism) has a way
for us to bind to the loaded Ruby without having to search the file
system.  Specifically, dlsym will search for symbols exported by
the initially loaded objects and any objects that were loaded as
global.  Ruby thankfully links against libruby such that we can
discover libruby's exports this way.  When libfacter is running
under Ruby, we should now reliably function under the same Ruby VM.
Merge pull request #90 from peterhuene/custom/facts

(CFACT-44) Bind to loaded Ruby (if present) instead of searching.