Add git clean up aliases
Add git clean up aliases

trim: used to prune unnecessary objects and perform optimisations on
the repository.

cleanup: used to remove all untracked files and directories, and clear
the stash.

bronxct1/dotfiles,sdillingham/dotfiles,senorflor/dotfiles,marc0uk/dotfiles,saclark/dotfiles,Wilto/dotfiles,SiTaggart/dotfiles,intiocean/dotfiles,jorik041/dotfiles,pertoyra/dotfiles,codfish/dotfiles,micahwood/linux-dotfiles,micahwood/linux-dotfiles,jmyser/dotfiles,seiryu9/dotfiles,jorik041/dotfiles,bronxct1/dotfiles,codfish/dotfiles,nessthehero/dotfiles,nessthehero/dotfiles,Stubby/dotfiles,lgaechter/dotfiles,zjr/dotfiles-osx,Stubby/dotfiles,necolas/dotfiles,micahwood/linux-dotfiles,micahwood/linux-dotfiles,Gastove/dotfiles,pmacom/dotfiles,seiryu9/dotfiles,jorik041/dotfiles,micahwood/linux-dotfiles,nick-thompson/dotfiles,SBoudrias/dotfiles,senorflor/linux-dotfiles