Merge pull request #95 from eddelbuettel/master

Sparser default installation
Add LICENSE.txt.
avoid incoming checks by running R CMD check with  _R_CHECK_CRAN_INCOMING_=FALSE
Update sample configuration to dump logs on failure
Merge pull request #106 from krlmlr/no-incoming

avoid incoming checks by running R CMD check with _R_CHECK_CRAN_INCOMING_=FALSE
Merge pull request #107 from richfitz/master

Update sample configuration to dump logs on failure
do not override externally set _R_CHECK_CRAN_INCOMING_ variable
test incoming checks
Merge pull request #109 from krlmlr/allow-check-incoming

Do not override externally set _R_CHECK_CRAN_INCOMING_ variable