CGDS / clean_case_list URL construction bug

[LiNk-NY]

Hi cBioPortal maintainers,

I get an error using the CGDS function in cgdsr.

cgds <- cgdsr::CGDS("http://www.cbioportal.org")
coad <- clean_case_list("coadread_tcga_pub", cgds)
Error in file(file, "rt")
  cannot open the connection to 'http://www.cbioportal.orgwebservice.do?cmd=getCaseLists&cancer_study_id=coadread_tcga_pub'

It seems like you should be using file.path internally instead of paste when constructing
the URL so that the argument without the forward-slash works ("http://www.cbioportal.org").

Regards,
Marcel