Sharing with users and groups doesn't work

[MMoudry3]

##Issue
Sharing with users or groups doesnt work under latest Chrome.

Steps to reproduce

1. Create a credential using Chrome web browser
2. Attempt to share it with a group or a user - not using link

Expected behaviour

When trying to share with other users and groups, the textbox 'Search users and groups' works like elsewhere in nextCloud.

Actual behaviour

There are no selections proposed, writing full name or username and clicking on plus just makes the textbox red.

Configuration

Operating system: Client WIndows 10, server ubuntu 16.04

Browser: Chrome 56.0.2924.87 (64-bit), Firefox

Extensions that might cause interference: None

Passman version: 2.0.2

Operating system: Windows 10

Web server:
Apache2

Database:
Mysql

PHP version:
7.0

cloud server: Nextcloud

cloud version: (see admin page or version.php)
11.01

Browser log

Browser log

``` Insert your browser log here, this could for example include:

a) The javascript console log
b) The network log
c) ...

</details>   


#### Cloud log
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The log has the name owncloud.log or nextcloud.log and is found in the data folder
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<details>
<summary>Cloud log</summary>

Insert your cloud log here

</details>


## Feature request

**User type**: Logged-in or public user

**User level**: Beginners, intermediate or advanced

### Description
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Please try to give as much information as you can about your request
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### Benefit / value
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Please explain how it could benefit users of the app, other apps or 3rd party services
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### Risk / caveats
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Please explain the risks and caveats associated with this request
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### Sponsorship
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This greatly accelerates the delivery of a feature
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**Are you a developer willing to implement this feature?**: yes/no

**Can you sponsor the development of this feature or do you know someone who can?**: yes/no

[brantje]

I think #242 is related

[animalillo]

Do the target user have created any vaults?
We have added a warning message on passman v2.1 which will be the next release

[MMoudry3]

Nope I don't think so, lemme try that

[MMoudry3]

yes, that fixed it however now the share button stays greyed...

[MMoudry3]

For me, I am admin the button ungreys itself, for other users it stays greyed