Bug #2752

Updated by Matthieu Decorde 10 months ago

Simplify R startup messages when:
* The R executable path is empty
* The R executable path point to a non-existing file
* The R executable path don't point a file
* The R executable path point a non executable file
* R was not started using the The R executable path

See externalized messages :
RCoreMessages.bind(RCoreMessages.error_cantFindRServeInPath, pathToRExecutable)
RCoreMessages.bind(RCoreMessages.error_RservePathNotPointingAFile, pathToRExecutable)
RCoreMessages.bind(RCoreMessages.error_cantExecuteRServe, pathToRExecutable)
RCoreMessages.bind(RCoreMessages.rserveNotStartedUsingTheP0Path, pathToRExecutable)