[Rd] help (using ?) does not handle trailing whitespace (PR#11537)

[rocket at google.com]

> ?agrep 
> 

Results in:

No documentation for 'agrep ' in specified packages and libraries:
you could try 'help.search("agrep ")'

There is white space after agrep, that ? doesn't ignore.


--please do not edit the information below--

Version:
 platform = i486-pc-linux-gnu
 arch = i486
 os = linux-gnu
 system = i486, linux-gnu
 status = 
 major = 2
 minor = 7.0
 year = 2008
 month = 04
 day = 22
 svn rev = 45424
 language = R
 version.string = R version 2.7.0 (2008-04-22)

Locale:
LC_CTYPE=en_US;LC_NUMERIC=C;LC_TIME=C;LC_COLLATE=C;LC_MONETARY=C;LC_MESSAGES=en_US;LC_PAPER=en_US;LC_NAME=C;LC_ADDRESS=C;LC_TELEPHONE=C;LC_MEASUREMENT=en_US;LC_IDENTIFICATION=C

Search Path:
 .GlobalEnv, package:stats, package:graphics, package:grDevices, package:utils, package:datasets, package:showStructure, package:Rcode, package:splus2R, package:methods, Autoloads, package:base