Fixes some stylistic issues in the network admin and adds some missing sanitisation and escaping. Also removes the version number from composer,json to fix composer installs.

Props to @cfoellmann and @spacedmonkey.

Fixes an issue with subdirectory installs where subdirectories mapped to a domain would retain the subfolder part of the URL. Understandably this was not desirable behaviour.

This is the main release before the v2 fork and contains all the following bundled functionality:

• SSO
• Admin UI - network only

In future the core plugin will only provide the domain mapping engine and will be supported by an ecosystem of related plugins including:

• SSO
• Admin UI - network & per site
• REST API
• Redirect handler

This is the main release before the v2 fork and contains all the following bundled functionality:

• SSO
• Admin UI - network only

In future the core plugin will only provide the domain mapping engine and will be supported by an ecosystem of related plugins including:

• SSO
• Admin UI - network & per site
• REST API
• Redirect handler