Fish Shell overrides some shell commands, such as `cd` and `ls` and
therefore some rules fail to match. The following aliases are excluded
by default:
* cd
* grep
* ls
* man
* open
To change them, one can use the `TF_OVERRIDDEN_ALIASES` environment
variable such as:
```
set TF_OVERRIDDEN_ALIASES 'cd,grep,ls'
```
Fix#262
891fbe7ed1