REBASE add DecryptActivity to handle decrypting anything we throw at it
DebugLogActivity: use monospace font for debug log view

I also ran the code formatter on it, hence the top change on text/textColor
REBASE add DecryptActivity to handle decrypting anything we throw at it
FileHandlerActivity: set up as central router for incoming Intents

* all ambigious Intents should be handled by FileHandlerActivity
* should be renamed to IncomingContentHandlerActivity
* all clear Intents go directly to the right Activity and skip this one
  (e.g. .sig, .pkr, .skr files and the OpenPGP MIME types)
* this also handles non-PGP files and content which the user intends to
  encrypt and/or sign

refs #1454 refs #1455 refs #1456 refs #1577
route content:// streams named *.pgp, secring.gpg, pubring.gpg to Import

* .pgp files are supposed to be application/pgp-keys
* secring.gpg and pubring.gpg are keyrings from ~/.gnupg