Initial QSfera import

Server/vendor/github.com/amoghe/go-crypt/README.md

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+go-crypt (`crypt`)
+==================
+
+[![Build Status](https://travis-ci.org/amoghe/go-crypt.svg)](https://travis-ci.org/amoghe/go-crypt)
+
+Package `crypt` provides go language wrappers around crypt(3). For further information on crypt see the
+[man page](http://man7.org/linux/man-pages/man3/crypt.3.html)
+
+If you have questions about how to use crypt (the C function), it is likely this is not the package you
+are looking for.
+
+**NOTE** Depending on the platform, this package provides a `Crypt` function that is backed by different
+flavors of the libc crypt. This is done by detecting the GOOS and trying to build using `crypt_r` (the GNU
+extension) when on linux, and wrapping around plain 'ol `crypt` (guarded by a global lock) otherwise.
+
+Example
+-------
+```go
+import (
+	"fmt"
+	"github.com/amoghe/go-crypt"
+)
+
+func main() {
+	md5, err := crypt.Crypt("password", "in")
+	if err != nil {
+		fmt.Errorf("error:", err)
+		return
+	}
+
+	sha512, err := crypt.Crypt("password", "$6$SomeSaltSomePepper$")
+	if err != nil {
+		fmt.Errorf("error:", err)
+		return
+	}
+
+	fmt.Println("MD5:", md5)
+	fmt.Println("SHA512:", sha512)
+}
+```
+
+A Note On "Salt"
+----------------
+
+You can find out more about salt [here](https://en.wikipedia.org/wiki/Salt_(cryptography))
+
+The hash algorithm can be selected via the salt string. Here is how to do it (relevant
+section from the man page):
+
+```
+   If salt is a character string starting with the characters
+   "$id$" followed by a string terminated by "$":
+
+       $id$salt$encrypted
+
+   then instead of using the DES machine, id identifies the
+   encryption method used and this then determines how the rest
+   of the password string is interpreted.  The following values
+   of id are supported:
+
+          ID  | Method
+          ─────────────────────────────────────────────────────────
+          1   | MD5
+          2a  | Blowfish (not in mainline glibc; added in some
+              | Linux distributions)
+          5   | SHA-256 (since glibc 2.7)
+          6   | SHA-512 (since glibc 2.7)
+
+   So $5$salt$encrypted is an SHA-256 encoded password and
+   $6$salt$encrypted is an SHA-512 encoded one.
+
+   "salt" stands for the up to 16 characters following "$id$" in
+   the salt.  The encrypted part of the password string is the
+   actual computed password.  The size of this string is fixed:
+
+   MD5     | 22 characters
+   SHA-256 | 43 characters
+   SHA-512 | 86 characters
+```
+
+Platforms
+---------
+
+This package has been tested on the following platforms:
+- ubuntu 14.04.2 (libc 2.19)
+- ubuntu 12.04.5 (libc 2.15)
+- centos         (libc 2.17)
+- fedora 22      (libc 2.21)
+
+All the platforms tested on have GNU libc (with extensions) so that the GOOS=linux always
+compiles the reentrant versions of the crypt function (`crypt_r`), and exposes it to go land.
+
+Other platforms (freebsd, netbsd) should also work (in theory) since their libc expose at least
+a posix compliant crypt function. On these platforms the fallback should compile and expose the
+'plain' (non reentrant, thus globally locked) crypt function.
+
+Unfortunately, I do not have access to machines that run anything other than Linux, hence the other
+platforms have not been tested, however I believe they should work just fine. If you can verify this
+(or provide a patch that fixes this), I would be grateful.
+
+TODO
+----
+* Find someone with access to *BSD system(s)
+
+License
+-------
+
+Released under the [MIT License](LICENSE)