[Feat]: add `-m` and `-S` flags to commit command

[andy Augustin]

Remark
-S flag has been implemented with #20

Describe the feature

Within git you are able to use -m and -S flags for the commit comand e.g.
git commit -S -m "feat(config): :rocket: (#20) map config with cmd options" -m "add a mapping between the config options and the commands"

would be nice if go-gitmoji-cli would also have those options.

Use Case

There is a hook available.
Sometimes people want to use the git commit command together with the hook. Therefore the message parts (type, scope, message, gitmoji) should be kept.

Also -S flag should be available to sign commits (sometimes this is not globally configured)

Proposed Solution

parse the messages and put the parts as initial values.

Acknowledgements

• I may be able to implement this feature request