dyld: Library not loaded: /usr/local/opt/icu4c/lib/libicui18n.57.dylib

hello,who can give me help? thanks.

### Output

```
➜  ~ phpbrew
dyld: Library not loaded: /usr/local/opt/icu4c/lib/libicui18n.57.dylib
  Referenced from: /Users/xujiajun/.phpbrew/php/php-5.6.26/bin/php
  Reason: image not found
```


### Expected Result

```
fix this issue

```


### Platform

OS:

    e.g. OS X 10.11.6
Running PHP: 

Installing PHP:

php-5.6.26
