change git merge alias 'gm' to 'gmg'

Author: eatradish

bashrc.d/.vcs_git

@@ -15,7 +15,7 @@ alias gco="git checkout"
 alias gcob="git checkout -b"
 alias gt="git stash"
 alias gta="git stash apply"
-alias gm="git merge"
+alias gmg="git merge"
 alias gr="git rebase"
 alias gl="git log --oneline --decorate --graph"
 alias gsh="git show"