docs: update wallet screenshots (#414)

* docs: update some core screenshots

* docs: update wallet creation screenshot

* docs: update description for core options main tab

* docs: update core options screen descriptions

* docs: update description for wallet repair tab

Author: thephez

docs/user/wallets/dashcore/img/linux/dash-name-wallet.png

@@ -274,17 +274,17 @@ Start Dash Core on system login
   option is effectively the same as starting Dash Core together with the
   operating system.
 
-Hide tray icon
-  When this option is enabled, Dash Core will not display an icon in the
-  system tray. This option cannot be selected at the same time as
+Show tray icon
+  When this option is enabled, Dash Core will display an icon in the
+  system tray. This option must be selected to enable
   **Minimize to the tray instead of the taskbar**.
 
 Minimize to the tray instead of the taskbar
   When this option is enabled and the Dash Core window is minimized, it
   will no longer appear in your taskbar as a running task. Instead, Dash
   Core will keep running in the background and can be re-opened from the
   Dash icon in the system tray (the area next to your system clock). This
-  option cannot be selected at the same time as **Hide tray icon**.
+  option can only be selected when **Show tray icon** is selected.
 
 Minimize on close
   When this option is enabled, clicking the X button in the top right
@@ -313,6 +313,10 @@ Number of script verification threads
   that number of processor cores, while setting a negative number will
   leave that number of processor cores free.
 
+Enable RPC Server
+  This option allows you or a third-party tool to communicate with the node
+  through command-line and JSON-RPC commands.
+
 Wallet tab
 ----------
 
@@ -327,6 +331,9 @@ as inputs with the Coin Control, CoinJoin and Masternode features.
 
    The Wallet tab of the Dash Core Options dialog
 
+Subtract fee from amount by default
+  Whether to set subtract fee from amount as default or not.
+
 Enable coin control features
   Your Dash Core wallet balance is actually the sum total of all
   addresses holding balance that are associated with your wallet. When
@@ -339,6 +346,9 @@ Enable coin control features
   different addresses in your wallet. See :ref:`here <coin-control>` for
   a more detailed explanation of Coin Control.
 
+Keep custom change address
+  Whether to keep the specified custom change address or not.
+  
 Show Masternodes tab
   Enabling this option causes Dash Core to display an additional
   Masternodes tab to the right of the Transactions tab. This option
@@ -435,6 +445,14 @@ Map port using UPnP
   routers and will allow you to connect to the Dash network without making
   any special settings on your router.
 
+Map port using NAT-PMP
+  This option causes Dash Core to automatically attempt to open and map
+  the client port on your router using
+  `NAT-PMP <https://en.wikipedia.org/wiki/NAT_Port_Mapping_Protocol>`__
+  (NAT Port Mapping Protocol). This feature is supported by most modern home
+  routers and will allow you to connect to the Dash network without making
+  any special settings on your router.
+
 Allow incoming connections
   This option causes your client to accept external connections. Since
   Dash is a peer-to-peer network and Dash Core is considered a full client
@@ -612,21 +630,6 @@ Rescan blockchain files 2
   Performs the same operation as *Rescan blockchain files 1* but scans from the
   genesis block instead of the wallet creation time.
 
-Recover transactions
-  The recover transactions commands can be used to remove unconfirmed
-  transactions from the memory pool. Your wallet will restart and rescan
-  the blockchain, recovering existing transactions and removing
-  unconfirmed transactions. Transactions may become stuck in an
-  unconfirmed state if there is a conflict in protocol versions on the
-  network during CoinJoin processing, for example, or if a
-  transaction is sent with insufficient fees when blocks are full.
-
-Upgrade wallet format
-  This command is available for very old wallets where an upgrade to the
-  wallet version is required in addition to an update to the wallet
-  software. You can view your current wallet version by running the
-  ``getwalletinfo`` command in the console.
-
 Rebuild index
   Discards the current blockchain and chainstate indexes (the database of
   unspent transaction outputs) and rebuilds it from existing block files.