keep empty dirs
create RStudio project
ignore nonstandard files for building
install ODBC
do r_binary_install
add dependency on RJDBC
testthat is only suggested
load xlsx package
integrate rJava into the Travis build

- R CMD javareconf
- installation of unixodbc-dev
- test that packages are actually installed
project.info via makeActiveBinding
Roxygenize
bugfix docs
Roxygenize
Bump version to 0.4-4