CreateKeyActivity: fix bad path for exported secret key backup

refs #1460
CreateKeyActivity: do not upload to keyserver by default

Since it is hard to undo the upload, this should not be on by default.
CreateKeyActivity: create properly formatted params to fix gpgme key gen

The parameters in the "params" string need to be in a specific order,
otherwise the ken gen process fails. gpgme does not give very specific
error messages, but since the data format is almost the same as
`gpg2 --gen-key myparamsfile`, its easy to test the params file there.

refs #1460
CreateKeyActivity: put entire gen-key process in try/catch block for clarity

This also makes it easy to do things like getCanonicalPath() without
having to add another try/catch block.

refs #1460
CreateKeyActivity: add ProgressDialog with status messages

A simple set of messages to show what stage the process is on.  This should
be expanded to get the progress output from gpg2 to give the user more
feedback, since the key gen process can take so long.

refs #1460
add "Settings" to the main menubar, with priority over "Debug Mode"
add "Send Key" debug method for uploading to the key server

This also moves the title strings to strings.xml and adds window messages
to the prompt dialog.
CreateKeyActivity: show gen-revoke as disabled since it doesn't work yet

refs #1372 refs #1481
CreateKeyActivity: return result, send broadcast, & finish upon completion

This adds a method that sends the setResult() for the calling Activity,
sends a broadcast to refresh the key view, and calls finish() to make
CreateKeyActivity disappear.  It also shows a Toast if it failed.

closes #1550