Merge #15818: [0.18] doc backports

a644780a2f7076d4705d4e0d3486c0df8424367d doc: Clarify RPC versioning (MarcoFalke)
194226f6798e59cfd871db0335e078101b165043 doc: describe onlynet option in doc/tor.md (Jon Atack)
6d2448ca8e8bbf326730e79a7e1d959b4e81a76e doc/dependencies: Fix typo libsrvg->librsvg (Luke Dashjr)
9c572e3b2160f3a2b78847bbdc839b7be35dffd7 doc: mention creating application support bitcoin folder on OSX (Jack Mallers)
c69138a0d6b4878dfb01030861753738179ef0a4 gitignore: add *.plist (clang-check) (James O'Beirne)
8f7cfb00964a9edfa6fc46c506dad4b9c24661bf gitignore: add *.dat (James O'Beirne)

Pull request description:

  Backports #15684, #15792, #15802,  #15809 to the `0.18` branch.

ACKs for commit a64478:

Tree-SHA512: 6ed524a7b94242f8a738710d4321b98b9e80d6625d384fd83280b38fcb6bb8c468bcec1d980789ad2f4c91a5629ffe5c5314a7353181f08884c5a081840431cc

5 files changed, 26 insertions, 3 deletions

diff --git a/.gitignore b/.gitignore
index 994d67402f..be784024a0 100644
--- a/.gitignore
+++ b/.gitignore
@@ -66,6 +66,7 @@ src/qt/bitcoin-qt.includes
 *.a
 *.pb.cc
 *.pb.h
+*.dat
 
 *.log
 *.trs
@@ -120,3 +121,6 @@ contrib/devtools/split-debug.sh
 
 # Output from running db4 installation
 db4/
+
+# clang-check
+*.plist
diff --git a/doc/JSON-RPC-interface.md b/doc/JSON-RPC-interface.md
index 982afd5d56..a0cfe84a3e 100644
--- a/doc/JSON-RPC-interface.md
+++ b/doc/JSON-RPC-interface.md
@@ -5,6 +5,18 @@ The headless daemon `bitcoind` has the JSON-RPC API enabled by default, the GUI
 option. In the GUI it is possible to execute RPC methods in the Debug Console
 Dialog.
 
+## Versioning
+
+The RPC interface might change from one major version of Bitcoin Core to the
+next. This makes the RPC interface implicitly versioned on the major version.
+The version tuple can be retrieved by e.g. the `getnetworkinfo` RPC in
+`version`.
+
+Usually deprecated features can be re-enabled during the grace-period of one
+major version via the `-deprecatedrpc=` command line option. The release notes
+of a new major release come with detailed instructions on what RPC features
+were deprecated and how to re-enable them temporarily.
+
 ## Security
 
 The RPC interface allows other programs to control Bitcoin Core,
diff --git a/doc/build-osx.md b/doc/build-osx.md
index 119896dc67..d28a3d97aa 100644
--- a/doc/build-osx.md
+++ b/doc/build-osx.md
@@ -82,6 +82,8 @@ Bitcoin Core is now available at `./src/bitcoind`
 
 Before running, you may create an empty configuration file:
 
+    mkdir -p "/Users/${USER}/Library/Application Support/Bitcoin"
+
     touch "/Users/${USER}/Library/Application Support/Bitcoin/bitcoin.conf"
 
     chmod 600 "/Users/${USER}/Library/Application Support/Bitcoin/bitcoin.conf"
diff --git a/doc/dependencies.md b/doc/dependencies.md
index e4be63772c..229f9ca742 100644
--- a/doc/dependencies.md
+++ b/doc/dependencies.md
@@ -17,7 +17,7 @@ These are the dependencies currently used by Bitcoin Core. You can find instruct
 | libevent | [2.1.8-stable](https://github.com/libevent/libevent/releases) | 2.0.22 | No |  |  |
 | libjpeg |  |  |  |  | [Yes](https://github.com/bitcoin/bitcoin/blob/master/depends/packages/qt.mk#L65) |
 | libpng |  |  |  |  | [Yes](https://github.com/bitcoin/bitcoin/blob/master/depends/packages/qt.mk#L64) |
-| libsrvg | |  |  |  |  |
+| librsvg | |  |  |  |  |
 | MiniUPnPc | [2.0.20180203](http://miniupnp.free.fr/files) |  | No |  |  |
 | OpenSSL | [1.0.1k](https://www.openssl.org/source) |  | Yes |  |  |
 | PCRE |  |  |  |  | [Yes](https://github.com/bitcoin/bitcoin/blob/master/depends/packages/qt.mk#L66) |
@@ -43,4 +43,4 @@ Some dependencies are not needed in all configurations. The following are some f
 * ZeroMQ is needed only with the `--with-zmq` option.
 
 #### Other
-* librsvg is only needed if you need to run `make deploy` on (cross-compliation to) macOS.
\ No newline at end of file
+* librsvg is only needed if you need to run `make deploy` on (cross-compilation to) macOS.
diff --git a/doc/tor.md b/doc/tor.md
index c46b7e9f60..cfb7f16666 100644
--- a/doc/tor.md
+++ b/doc/tor.md
@@ -16,7 +16,7 @@ outgoing connections, but more is possible.
 
 	-onion=ip:port  Set the proxy server to use for Tor hidden services. You do not
 	                need to set this if it's the same as -proxy. You can use -noonion
-	                to explicitly disable access to hidden service.
+	                to explicitly disable access to hidden services.
 
 	-listen         When using -proxy, listening is disabled by default. If you want
 	                to run a hidden service (see next section), you'll need to enable
@@ -27,6 +27,11 @@ outgoing connections, but more is possible.
 	-seednode=X     SOCKS5. In Tor mode, such addresses can also be exchanged with
 	                other P2P nodes.
 
+	-onlynet=onion  Make outgoing connections only to .onion addresses. Incoming
+	                connections are not affected by this option. This option can be
+	                specified multiple times to allow multiple network types, e.g.
+	                ipv4, ipv6, or onion.
+
 In a typical situation, this suffices to run behind a Tor proxy:
 
 	./bitcoind -proxy=127.0.0.1:9050