Infer app_name from publish profile if provided, make app_name optional

[moselhy]

If a publish profile is provided like this, the app_name action parameter can be inferred from values like userName.slice(1), publishUrl.split('.')[0], instead of being a required parameter.

<publishData>
    <publishProfile profileName="exampleappname - Web Deploy" publishMethod="MSDeploy"
        publishUrl="exampleappname.scm.azurewebsites.net:443" msdeploySite="exampleappname"
        userName="$exampleappname"
        userPWD="randompasswordxyz123"
        destinationAppUrl="https://exampleappname.azurewebsites.net" SQLServerDBConnectionString=""
        mySQLDBConnectionString="" hostingProviderForumLink=""
        controlPanelLink="http://windows.azure.com" webSystem="WebSites">
        <databases />
    </publishProfile>
    <publishProfile profileName="exampleappname - FTP" publishMethod="FTP"
        publishUrl="ftps://waws-prod-ln1-045.ftp.azurewebsites.windows.net/site/wwwroot"
        ftpPassiveMode="True" userName="exampleappname\$exampleappname"
        userPWD="randompasswordxyz123"
        destinationAppUrl="https://exampleappname.azurewebsites.net" SQLServerDBConnectionString=""
        mySQLDBConnectionString="" hostingProviderForumLink=""
        controlPanelLink="http://windows.azure.com" webSystem="WebSites">
        <databases />
    </publishProfile>
    <publishProfile profileName="exampleappname - Zip Deploy" publishMethod="ZipDeploy"
        publishUrl="exampleappname.scm.azurewebsites.net:443" userName="$exampleappname"
        userPWD="randompasswordxyz123"
        destinationAppUrl="https://exampleappname.azurewebsites.net" SQLServerDBConnectionString=""
        mySQLDBConnectionString="" hostingProviderForumLink=""
        controlPanelLink="http://windows.azure.com" webSystem="WebSites">
        <databases />
    </publishProfile>
</publishData>