can't install keybase on windows with msys2

Hey guys.

I'm trying to install keybase on windows 7 in the msys2 environment:

```
$ node --version
v0.10.32

$ npm --version
1.4.28

$ gpg --version
gpg (GnuPG) 1.4.18
```

Here's what happens:

```
$ keybase-installer
info: Made temporary directory: C:\Users\celliso2\AppData\Local\Temp\keybase_install_9qw3ggaMNh7qLws_iK_9wQ
info: cleaning up tmpdir C:\Users\celliso2\AppData\Local\Temp\keybase_install_9qw3ggaMNh7qLws_iK_9wQ
error: exit code 2
warn: gpg: invalid key resource URL `C:\Users\celliso2\AppData\Roaming\.keybase-installer\keyring\secring.gpg'
warn: gpg: keyblock resource `(null)': general error
warn: gpg: invalid key resource URL `C:\Users\celliso2\AppData\Roaming\.keybase-installer\keyring\pubring.gpg'
warn: gpg: keyblock resource `(null)': general error
warn: gpg: fatal: can't create `/home/celliso2/.gnupg/C:\Users\celliso2\AppData\Roaming\.keybase-installer\keyring\trustdb.gpg': No such file or directory
warn: secmem usage: 0/0 bytes in 0/0 blocks of pool 0/65536

$ keybase
bash: keybase: command not found

```

The two files it's looking for exist, but are empty:

```
$ ls -all 'C:\Users\celliso2\AppData\Roaming\.keybase-installer\keyring\pubring.gpg'
-rw-r--r-- 1 celliso2 None 0 Jan 26 16:55 C:\Users\celliso2\AppData\Roaming\.keybase-installer\keyring\pubring.gpg

$ ls -all 'C:\Users\celliso2\AppData\Roaming\.keybase-installer\keyring\secring.gpg'
-rw-r--r-- 1 celliso2 None 0 Jan 26 16:55 C:\Users\celliso2\AppData\Roaming\.keybase-installer\keyring\secring.gpg
```

But the other path `/home/celliso2/.gnupg/C:\Users\celliso2\AppData\Roaming\.keybase-installer\keyring\trustdb.gpg` is clearly borked.

Anything else I can send to help figure this out?

Start by reproducing the keybase-installer failure in Windows 7 under MSYS2 with the reported Node.js, npm, and GnuPG versions. Investigate how the Windows keyring paths are passed to GnuPG; done means installation completes and the keybase command is available without the malformed trustdb path.

Written by the indexing model from the issue text.