patch 8.0.1108: cannot specify mappings for the terminal window

Problem:    Cannot specify mappings for the terminal window.
Solution:   Add the :tmap command and associated code.  (Jacob Askeland,
            closes #2073)

runtime/doc/map.txt

@@ -55,6 +55,7 @@ modes.
 :im[ap]	{lhs} {rhs}		|mapmode-i|		*:im* *:imap*
 :lm[ap]	{lhs} {rhs}		|mapmode-l|		*:lm* *:lmap*
 :cm[ap]	{lhs} {rhs}		|mapmode-c|		*:cm* *:cmap*
+:tm[ap]	{lhs} {rhs}		|mapmode-t|		*:tm* *:tmap*
 			Map the key sequence {lhs} to {rhs} for the modes
 			where the map command applies.  The result, including
 			{rhs}, is then further scanned for mappings.  This
@@ -71,6 +72,7 @@ modes.
 :ino[remap] {lhs} {rhs}		|mapmode-i|	*:ino* *:inoremap*
 :ln[oremap] {lhs} {rhs}		|mapmode-l|	*:ln*  *:lnoremap*
 :cno[remap] {lhs} {rhs}		|mapmode-c|	*:cno* *:cnoremap*
+:tno[remap] {lhs} {rhs}		|mapmode-t|	*:tno* *:tnoremap*
 			Map the key sequence {lhs} to {rhs} for the modes
 			where the map command applies.  Disallow mapping of
 			{rhs}, to avoid nested and recursive mappings.  Often
@@ -87,6 +89,7 @@ modes.
 :iu[nmap] {lhs}			|mapmode-i|		*:iu*   *:iunmap*
 :lu[nmap] {lhs}			|mapmode-l|		*:lu*   *:lunmap*
 :cu[nmap] {lhs}			|mapmode-c|		*:cu*   *:cunmap*
+:tu[nmap] {lhs}			|mapmode-t|		*:tu*   *:tunmap*
 			Remove the mapping of {lhs} for the modes where the
 			map command applies.  The mapping may remain defined
 			for other modes where it applies.
@@ -105,6 +108,7 @@ modes.
 :imapc[lear]			|mapmode-i|		*:imapc*  *:imapclear*
 :lmapc[lear]			|mapmode-l|		*:lmapc*  *:lmapclear*
 :cmapc[lear]			|mapmode-c|		*:cmapc*  *:cmapclear*
+:tmapc[lear]			|mapmode-t|		*:tmapc*  *:tmapclear*
 			Remove ALL mappings for the modes where the map
 			command applies.  {not in Vi}
 			Use the <buffer> argument to remove buffer-local
@@ -121,6 +125,7 @@ modes.
 :im[ap]				|mapmode-i|
 :lm[ap]				|mapmode-l|
 :cm[ap]				|mapmode-c|
+:tm[ap]				|mapmode-t|
 			List all key mappings for the modes where the map
 			command applies.  Note that ":map" and ":map!" are
 			used most often, because they include the other modes.
@@ -135,6 +140,7 @@ modes.
 :im[ap] {lhs}			|mapmode-i|		*:imap_l*
 :lm[ap] {lhs}			|mapmode-l|		*:lmap_l*
 :cm[ap] {lhs}			|mapmode-c|		*:cmap_l*
+:tm[ap] {lhs}			|mapmode-t|		*:tmap_l*
 			List the key mappings for the key sequences starting
 			with {lhs} in the modes where the map command applies.
 			{not in Vi}
@@ -318,6 +324,7 @@ Overview of which map command works in which mode.  More details below.
 :imap  :inoremap :iunmap    Insert
 :lmap  :lnoremap :lunmap    Insert, Command-line, Lang-Arg
 :cmap  :cnoremap :cunmap    Command-line
+:tmap  :tnoremap :tunmap    Terminal-Job
 
 
     COMMANDS				      MODES ~
@@ -358,6 +365,10 @@ Therefore the ":map" and ":map!" commands enter and display mappings for
 several modes.  In Vim you can use the ":nmap", ":vmap", ":omap", ":cmap" and
 ":imap" commands to enter mappings for each mode separately.
 
+							*mapmode-t*
+The terminal mappings are used in a terminal window, when typing keys for the
+job running in the terminal.  See |terminal-typing|.
+
 							*omap-info*
 Operator-pending mappings can be used to define a movement command that can be
 used with any operator.  Simple example: ":omap { w" makes "y{" work like "yw"
@@ -418,6 +429,7 @@ When listing mappings the characters in the first two columns are:
 	i	Insert
 	l	":lmap" mappings for Insert, Command-line and Lang-Arg
 	c	Command-line
+        t       Terminal-Job
 
 Just before the {rhs} a special character can appear:
 	*	indicates that it is not remappable

runtime/doc/terminal.txt

@@ -1,4 +1,4 @@
-*terminal.txt*	For Vim version 8.0.  Last change: 2017 Sep 13
+*terminal.txt*	For Vim version 8.0.  Last change: 2017 Sep 14
 
 
 		  VIM REFERENCE MANUAL	  by Bram Moolenaar
@@ -38,7 +38,7 @@ output from the job, also while editing in another window.
 
 
 Typing ~
-
+							*terminal-typing*
 When the keyboard focus is in the terminal window, typed keys will be sent to
 the job.  This uses a pty when possible.  You can click outside of the
 terminal window to move keyboard focus elsewhere.
@@ -79,6 +79,10 @@ do.  For simple commands this causes a SIGINT to be sent to the job, which
 would end it.  Other commands may ignore the SIGINT or handle the CTRL-C
 themselves (like Vim does).
 
+To change the keys you type use terminal mode mappings, see |:tmap|.
+These are defined like any mapping, but apply only when typing keys that are
+sent to the job running in the terminal.
+
 
 Size and color ~
 
@@ -221,6 +225,10 @@ mode.
 Use CTRL-W N (or 'termkey' N) to switch to Terminal-Normal mode.  Now the
 contents of the terminal window is under control of Vim, the job output is
 suspended.  CTRL-\ CTRL-N does the same.
+
+Terminal-Job mode is where |tmap| mappings are applied. Keys sent by
+|term_sendkeys()| are not subject to tmap, but keys from |feedkeys()| are.
+
 							*E946*
 In Terminal-Normal mode you can move the cursor around with the usual Vim
 commands, Visually mark text, yank text, etc.  But you cannot change the
@@ -301,7 +309,7 @@ inspects the resulting screen state.
 
 Functions ~
 
-term_sendkeys()		send keystrokes to a terminal
+term_sendkeys()		send keystrokes to a terminal (not subject to tmap)
 term_wait()		wait for screen to be updated
 term_scrape()		inspect terminal screen