Add authfile, cert-dir and creds params to build

Signed-off-by: TomSweeneyRedHat <tsweeney@redhat.com>

Closes: #280
Approved by: mheon

docs/podman-build.1.md

@@ -24,6 +24,11 @@ to do the actual building.
 
 ## OPTIONS
 
+**--authfile** *path*
+
+Path of the authentication file. Default is ${XDG_RUNTIME\_DIR}/containers/auth.json, which is set using `podman login`.
+If the authorization state is not found there, $HOME/.docker/config.json is checked, which is set using `docker login`.
+
 **--build-arg** *arg=value*
 
 Specifies a build argument and its value, which will be interpolated in
@@ -31,6 +36,16 @@ instructions read from the Dockerfiles in the same way that environment
 variables are, but which will not be added to environment variable list in the
 resulting image's configuration.
 
+**--cert-dir** *path*
+
+Use certificates at *path* (*.crt, *.cert, *.key) to connect to the registry
+
+**--creds** *creds*
+
+The [username[:password]] to use to authenticate with the registry if required.
+If one or both values are not supplied, a command line prompt will appear and the
+value can be entered.  The password is entered without echo.
+
 **-f, --file** *Dockerfile*
 
 Specifies a Dockerfile which contains instructions for building the image,
@@ -96,6 +111,12 @@ podman build --tls-verify=true -t imageName -f Dockerfile.simple
 
 podman build --tls-verify=false -t imageName .
 
+podman bud --runtime-flag log-format=json .
+
+podman bud --runtime-flag debug .
+
+podman bud --authfile /tmp/auths/myauths.json --cert-dir ~/auth --tls-verify=true --creds=username:password -t imageName -f Dockerfile.simple
+
 ## SEE ALSO
 podman(1), buildah(1)