Add working directory status to CLI status

This is displayed in the watched repository table in the CLI status.
In the process I have also extracted the code for checking if the working
directory is dirty into its own method, and test it.
Add the magic encoding string to all the files

This is a good practises in general, but hopefully it will also make
the UTF-8 characters that I wish to use in the CLI work consistently
across Ruby1.9 and Ruby2.0.
Add sync status to CLI status

This is also displayed in the watched repository table in the CLI
status. Shows if the repository needs to be pushed or merged.

Not using any fancy UTF-8 symbols for the status as they will not always
work in ruby1.9. Maybe try this later when 1.9 support is dropped.
Small refactoring of the push and merge guards

I think that this makes the logic of the when to push or sync a little
easier to read.
Increase all timeouts to 20 seconds

Which hopefully will avoid failures due to slow execution on Travis.
Added a changelog entry for the repository status
Merge pull request #86 from acant/feature/status

Added repository status to the CLI status display.