Fix the support of installation hook for fisher

0.0.5

run install scripts in the shell init

Support installation hook for fisher

0.0.4

emit <plugin-name>_install event when build derivation, as fisher does

emit <plugin>_install

0.0.3

Emit install event

0.0.2

Merge branch 'master' of https://github.com/takagiy/nixos-declarative…

0.0.1

initial commit