Fix long option format on docs.podman.io

Escape the two dashes, otherwise they are combined into one long dash.
I tested that this change is safe and still renders correctly on github
and with the man pages.

This commit also contains a small change to make it build locally.
Assuming you have the dependencies installed you can do:
```
cd docs
make html
```
Preview the html files in docs/build/html with
`python -m http.server 8000 --directory build/html`.

Fixes containers/podman.io#373

Signed-off-by: Paul Holzinger <paul.holzinger@web.de>

1 files changed, 11 insertions, 11 deletions

diff --git a/docs/source/markdown/podman-push.1.md b/docs/source/markdown/podman-push.1.md
index f42ee1020..1bef7ebdb 100644
--- a/docs/source/markdown/podman-push.1.md
+++ b/docs/source/markdown/podman-push.1.md
@@ -54,7 +54,7 @@ Images are pushed from those stored in local image storage.
 
 ## OPTIONS
 
-#### **--authfile**=*path*
+#### **\-\-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`.
@@ -62,49 +62,49 @@ If the authorization state is not found there, $HOME/.docker/config.json is chec
 Note: You can also override the default path of the authentication file by setting the REGISTRY\_AUTH\_FILE
 environment variable. `export REGISTRY_AUTH_FILE=path`
 
-#### **--creds**=*[username[:password]]*
+#### **\-\-creds**=*[username[:password]]*
 
 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.
 
-#### **--cert-dir**=*path*
+#### **\-\-cert-dir**=*path*
 
 Use certificates at *path* (\*.crt, \*.cert, \*.key) to connect to the registry.
 Default certificates directory is _/etc/containers/certs.d_. (This option is not available with the remote Podman client)
 
-#### **--compress**
+#### **\-\-compress**
 
 Compress tarball image layers when pushing to a directory using the 'dir' transport. (default is same compression type, compressed or uncompressed, as source)
 Note: This flag can only be set when using the **dir** transport
 
-#### **--digestfile** *Digestfile*
+#### **\-\-digestfile** *Digestfile*
 
 After copying the image, write the digest of the resulting image to the file.  (This option is not available with the remote Podman client)
 
-#### **--disable-content-trust**
+#### **\-\-disable-content-trust**
 
 This is a Docker specific option to disable image verification to a Docker
 registry and is not supported by Podman.  This flag is a NOOP and provided
 solely for scripting compatibility.
 
-#### **--format**, **-f**=*format*
+#### **\-\-format**, **-f**=*format*
 
 Manifest Type (oci, v2s2, or v2s1) to use when pushing an image.
 
-#### **--quiet**, **-q**
+#### **\-\-quiet**, **-q**
 
 When writing the output image, suppress progress output
 
-#### **--remove-signatures**
+#### **\-\-remove-signatures**
 
 Discard any pre-existing signatures in the image. (This option is not available with the remote Podman client)
 
-#### **--sign-by**=*key*
+#### **\-\-sign-by**=*key*
 
 Add a signature at the destination using the specified key. (This option is not available with the remote Podman client)
 
-#### **--tls-verify**=*true|false*
+#### **\-\-tls-verify**=*true|false*
 
 Require HTTPS and verify certificates when contacting registries (default: true). If explicitly set to true,
 then TLS verification will be used. If set to false, then TLS verification will not be used. If not specified,