I just realized that git is using vim as text editor (hope it is possible to change to nano or equivalent). Anyway, as for now I guess I better just learn som basic vim commands.
http://heather.cs.ucdavis.edu/~matloff/UnixAndC/Editors/ViIntro.html saved me.
The most important commands to remember are:
i - enter "insert mode"
a - enter "append mode"
ESC - leave "insert" or "append mode"
x - delete one character
dd - delete one line (and store it in clipboard)
ZZ - Save and close
ZQ - Close w/o saving
(Most of them should be used when yo are NOT in insert/append mode)
There's also a nice printable cheatsheet, here: http://www.viemu.com/vi-vim-cheat-sheet.gif