updated for version 7.4.234

Problem:    Can't get the command that was used to start Vim.
Solution:   Add v:progpath. (Viktor Kojouharov)

runtime/doc/eval.txt

@@ -1556,6 +1556,12 @@ v:profiling	Normally zero.	Set to one after using ":profile start".
 v:progname	Contains the name (with path removed) with which Vim was
 		invoked.  Allows you to do special initialisations for |view|,
 		|evim| etc., or any other name you might symlink to Vim.
+		Read-only.
+
+					*v:progpath* *progpath-variable*
+v:progpath	Contains the command with which Vim was invoked, including the
+		path.  Useful if you want to message a Vim server using a
+		|--remote-expr|.
 		Read-only.
 
 					*v:register* *register-variable*