Added types to #have_func calls
Fixes two "unused variable" inclusion warnings

lib/nmatrix/nmatrix.rb:566:
warning: assigned but unused variable - new_cap

lib/nmatrix/lapack.rb:196:
warning: assigned but unused variable - result
Reverted a few extconf changes
Removed another inclusion warning
Fixed problems with extconf default library paths
Added args to have_func calls
Merge branch 'fixing_warnings' of https://github.com/andrewcsmith/nmatrix into andrewcsmith-fixing_warnings
Merge pull request #238 from andrewcsmith/fixing_warnings

Fixed issues with the #have_func calls and the "unused variable" warnings
Merge branch 'andrewcsmith-fixing_warnings'
Include all ext/ files in docs

Some files weren't being added to the generated documentation because
the globs weren't general enough. It's best to add every file under ext/
and lib/ and remove the constants from `ttable_helper.rb` manually via
:nodoc:.
Hide constants with :nodoc:

`NMGCHolder` class is an important part of NMatrix's internals, but
it should definitely be hidden in the generated documentation.

The RSpec extension (to `BeWithin`) is only used during testing and
shouldn't be shown on the documentation. I selectively excluded its file
in the Rakefile's RDoc task.

Lots of other classes and modules were also :nodoc:'d.
Documentation for YALE_GROWTH_CONSTANT

Using C-style comments make for better RDoc style. And not including the
constant's name in the `Document-const` directive turns out to generate
a cleaner documentation.
More documentation for NMatrix::[] / N::[]

I just added one more example and made the call-seq: instruction a bit
more informative.

I also removed :nodoc: directives from `ttable_helper.rb` and removed
the file from RDoc generation. It seems cleaner that way.
Add documentation to stype shortcuts
Add documentation for specialized concat methods
Remove unnecessary :nodoc:s

It's much easier to remove files from RDoc generation instead of adding
`:nodoc:` to every method, class and module in it.
Add some documentation to the NMatrix class
Documenting NMatrix::IO modules and classes

The most important parts for the public are the modules for loading
matrices from specific formats -- MatrixMarket, PCD and Matlab. It isn't
necessary to show their internals, which just pollute the API
documentation.

I also removed autoloads for NMatrix::IO classes and put `require`s in
`lib/nmatrix.rb`. This is easier and the speed difference isn't really
relevant for us -- those extra modules aren't going to significantly
slow down a program.