patch 8.0.0846: cannot get the name of the pty of a job

Problem:    Cannot get the name of the pty of a job.
Solution:   Add the "tty" entry to the job info. (Ozaki Kiichi, closes #1920)
            Add the term_gettty() function.
diff --git a/runtime/doc/eval.txt b/runtime/doc/eval.txt
index cbe5565..ff9dac2 100644
--- a/runtime/doc/eval.txt
+++ b/runtime/doc/eval.txt
@@ -1,4 +1,4 @@
-*eval.txt*	For Vim version 8.0.  Last change: 2017 Aug 01
+*eval.txt*	For Vim version 8.0.  Last change: 2017 Aug 03
 
 
 		  VIM REFERENCE MANUAL	  by Bram Moolenaar
@@ -2376,6 +2376,7 @@
 term_getsize({buf})		List	get the size of a terminal
 term_getstatus({buf})		String	get the status of a terminal
 term_gettitle({buf})		String	get the title of a terminal
+term_gettty({buf})		String	get the tty name of a terminal
 term_list()			List	get the list of terminal buffers
 term_scrape({buf}, {row})	List	get row of a terminal screen
 term_sendkeys({buf}, {keys})	none	send keystrokes to a terminal
@@ -5192,6 +5193,8 @@
 		Returns a Dictionary with information about {job}:
 		   "status"	what |job_status()| returns
 		   "channel"	what |job_getchannel()| returns
+		   "process"	process ID
+		   "tty"	controlling terminal name, empty when none
 		   "exitval"	only valid when "status" is "dead"
 		   "exit_cb"	function to be called on exit
 		   "stoponexit"	|job-stoponexit|
@@ -7930,6 +7933,7 @@
 term_getjob({buf})					*term_getjob()*
 		Get the Job associated with terminal window {buf}.
 		{buf} is used as with |term_getsize()|.
+		Returns |v:null| when there is no job.
 
 term_getline({buf}, {row})				*term_getline()*
 		Get a line of text from the terminal window of {buf}.
@@ -7943,9 +7947,9 @@
 		numbers: [rows, cols].  This is the size of the terminal, not
 		the window containing the terminal.
 
-		{buf} must be the buffer number of a terminal window. If the
-		buffer does not exist or is not a terminal window, an empty
-		list is returned.
+		{buf} must be the buffer number of a terminal window.  Use an
+		empty string for the current buffer.  If the buffer does not
+		exist or is not a terminal window, an empty list is returned.
 
 term_getstatus({buf})					*term_getstatus()*
 		Get the status of terminal {buf}. This returns a comma
@@ -7967,6 +7971,11 @@
 		buffer does not exist or is not a terminal window, an empty
 		string is returned.
 
+term_gettty({buf})					*term_gettty()*
+		Get the name of the controlling terminal associated with
+		terminal window {buf}.
+		{buf} is used as with |term_getsize()|.
+
 term_list()						*term_list()*
 		Return a list with the buffer numbers of all buffers for
 		terminal windows.
@@ -7982,7 +7991,7 @@
 		    "chars"	character(s) at the cell
 		    "fg"	foreground color as #rrggbb
 		    "bg"	background color as #rrggbb
-		    "attr"	attributes of the cell, use term_getattr()
+		    "attr"	attributes of the cell, use |term_getattr()|
 		    		to get the individual flags
 		    "width"	cell width: 1 or 2