Dotdrop

* fix import bug

* add support for *pre*/*post* actions thanks to ziirish
* fix include bug
* fix updating directory
* fix importing dotfile and unique key
* adding bash scripts tests

* make sure `config` entry settings in the config file have defaults when parsed
* add `banner` option in config file

add `-b --no-banner` switch to hide banner

* fix relative path computation (29)
* add debug mode and output
* refactoring

* ensure directory tree exists when symlink (thanks lyze237)
* properly handle exception when destination is not a directory (and expected to be)
* also deploy when file rights have changed (useful for `chmod +x` changes and similar)