copy, move, mirror: Support --json and --json-progress.

doc/git-annex-copy.mdwn

@@ -72,6 +72,15 @@ Copies the content of files from or to another remote.
   The [[git-annex-matching-options]](1)
   can be used to specify files to copy.
 
+* `--json`
+
+  Enable JSON output. This is intended to be parsed by programs that use
+  git-annex. Each line of output is a JSON object.
+
+* `--json-progress`
+
+  Include progress objects in JSON output.
+
 # SEE ALSO
 
 [[git-annex]](1)

doc/git-annex-mirror.mdwn

@@ -66,6 +66,15 @@ contents. Use [[git-annex-sync]](1) for that.
   The [[git-annex-matching-options]](1)
   can be used to specify files to mirror.
 
+* `--json`
+
+  Enable JSON output. This is intended to be parsed by programs that use
+  git-annex. Each line of output is a JSON object.
+
+* `--json-progress`
+
+  Include progress objects in JSON output.
+
 # SEE ALSO
 
 [[git-annex]](1)

doc/git-annex-move.mdwn

@@ -55,6 +55,15 @@ Moves the content of files from or to another remote.
   The [[git-annex-matching-options]](1)
   can be used to specify files to move.
 
+* `--json`
+
+  Enable JSON output. This is intended to be parsed by programs that use
+  git-annex. Each line of output is a JSON object.
+
+* `--json-progress`
+
+  Include progress objects in JSON output.
+
 # SEE ALSO
 
 [[git-annex]](1)

doc/todo/interface_to_the___34__progress__34___of_annex_operations.mdwn

@@ -12,4 +12,8 @@ Related:
 > relay the progress messages when datalad is doing a nested retrieval, I
 > suppose.) --[[Joey]]
 
->> [[done]]; --json-progress implemented. --[[Joey]]
+>> [[done]]; --json-progress implemented. I limited the frequency of json
+>> progress items to 10 per second max, and it's typically only 1 per
+>> second or less, so didn't implement
+>> --json-progress=N to tune it. Also added --json and --json-progress to
+>> copy, move, mirror commands. --[[Joey]]