Make deployed_version.txt editor friendly

[AntonEvers]

Description

In production environments with a CDN for static files it comes in handy that you can force a browser cache refresh by changing the number manually without having to go into maintenance for a full deploy.

If you edit the pub/static/deployed_version.txt with vim, nano or echo '123456789' > pub/static/deployed_version.txt you can unintentionally create a newline at the end of the file.
This will result in:

    var BASE_URL = 'https://magento2.dev/sitemanager/admin/index/index/key/ec38dd3ded42b71db14166d6bcdfc56d4e7d4b7801b9808373ae4b3563b65513/';
    var FORM_KEY = 'dKArsQU6NhimXr6Z';
    var require = {
        "baseUrl": "https://magento2.dev/pub/static/version1492766286
/adminhtml/Magento/backend/en_US"
    };

With that baseUrl all resources using baseUrl will return the 404 page.

Adding a simple trim() here will remove that risk.

Manual testing scenarios

1. edit the pub/static/deployed_version.txt with vim in a shop that is in production mode
2. see the admin and frontend throw many js errors

Contribution checklist

• Pull request has a meaningful description of its purpose
• All commits are accompanied by meaningful commit messages
• All new or changed code is covered with unit/integration tests (if applicable)
• All automated tests passed successfully (all builds on Travis CI are green)

[ishakhsuvarov]

@ajpevers Isn't it better to add some command/option to the deploy command to refresh the version?

[AntonEvers]

@ishakhsuvarov I think a option in the deploy command would be best indeed. An extra command would clutter the bin/magento command list I fear. I'll work on a PR with the extra option. Maybe --refresh-version-only? Would that cover the option well enough? English is not my first language.

[ishakhsuvarov]

@ajpevers Thank you. Looks good to me for now.

[ishakhsuvarov]

@ajpevers Closing this for now due to inactivity. Please reopen and update this PR or create a new one if you wish to continue.
Thanks.

[mengbo123456]

# now i know why can't linking style ,but i don't know why this?
because install path no version1499055289 folder ,and i add it style work



but i don't know why it can't add version1499055289 folder itself in During the installation process

[AntonEvers]

Hello @mengbo123456,

You do not have to create the versionXXXXXXXXXX folder.
Magento also does not have to create the folder.

Please look at this line in the pub/static/.htaccess file: https://github.com/magento/magento2/blob/develop/pub/static/.htaccess#L16

It rewrites urls like https://example.com/pub/static/version1234567890/some/file.jpg to https://example.com/pub/static/some/file.jpg.
So Magento will actually return pub/static/some/file.jpg instead of pub/static/version1234567890/some/file.jpg.

So if one of your files is not found:
in developer mode: rm -r var/view_preprocessed/* pub/static/* var/cache/* var/page_cache/* and reload the page
in production mode: see http://devdocs.magento.com/guides/v2.1/config-guide/cli/config-cli-subcommands-static-view.html#config-cli-subcommands-xlate-dict for Magento 2.1 or http://devdocs.magento.com/guides/v2.0/config-guide/cli/config-cli-subcommands-static-view.html#config-cli-subcommands-xlate-dict for Magento 2.0