plumb/basic: allow . in http names
 [rsc] --rw-rw-r-- M 128579 glenda sys 2878 Mar 31 09:10 sys/lib/plumb/basic
	/n/sourcesdump/2006/0331/plan9/sys/lib/plumb/basic:9,15 - 
	/n/sourcesdump/2006/0401/plan9/sys/lib/plumb/basic:9,15
	  
	  # cheap http/gif,jpeg,ps,pdf renderer
	  type is text
	- data matches '(https?|ftp|file|gopher|mailto|news|nntp|telnet|wais|prospero)://[a-zA-Z0-9_@\-]+([.:][a-zA-Z0-9_@\-]+)*/?[a-zA-Z0-9_?,%#~&/\-+=]+([:.][a-zA-Z0-9_?,%#~&/\-+=]+)*\.(jpe?g|JPE?G|gif|GIF|ps|PS|pdf|PDF|png|PNG)'
	+ data matches '(https?|ftp|file|gopher|mailto|news|nntp|telnet|wais|prospero)://[a-zA-Z0-9_@\-]+([.:][a-zA-Z0-9_@\-]+)*/?[a-zA-Z0-9_?.,%#~&/\-+=]+([:.][a-zA-Z0-9_?,%#~&/\-+=]+)*\.(jpe?g|JPE?G|gif|GIF|ps|PS|pdf|PDF|png|PNG)'
	  plumb start rc -c 'hget '$0' | page -w'
	  
	  # rtf files go to wdoc2txt