move to_ container conversion out of view:: namespace; other naming changes
view::filter -> view::remove_if, action::erase_if -> action::remove_if
add view::partial_sum and tests
fix oops
initial doxygen commit
use https authentication on gh-pages submodule
group doxygen output into core, algorithms, views, action, utilities, and metaprogramming
Merge pull request #76 from ericniebler/doxygen

Add a doc target that uses doxgen to generate users doc and reference section
doxygen comments for metaprogramming facilities
better doxygen output for the algorithms
better doxygen output for the views and utility modules
add closed iota view form, fix bug in slice view, better doxygen for actions
fix clang+libc++ build break
rename join view to concat, flatten view to join
better compiler error messages when the views and actions are used incorrectly
add view::group_by and tests
add view::empty
view::split and tests
fix bug in join view
fix bugs and add tests for view::tokenize