Do not export what is not necessary

These variables only make sense in interactive bash session where we
always re-read .bashrc anyway.

dotfiles/bash/main.bashrc

 ### BASH ###
 ### '''' ###
 
-export HISTCONTROL=erasedups
-export HISTIGNORE="$HISTIGNORE:ls:ll:la:cd"
-export HISTIGNORE="$HISTIGNORE:git dc:git st"
+HISTCONTROL=erasedups
+HISTIGNORE="$HISTIGNORE:ls:ll:la:cd"
+HISTIGNORE="$HISTIGNORE:git dc:git st"
 #export HISTIGNORE="$HISTIGNORE:se *:sc *"
-export HISTSIZE=-1
-export HISTFILESIZE=100000
-export GLOBIGNORE=.:..
+HISTSIZE=-1
+HISTFILESIZE=100000
+GLOBIGNORE=.:..
 
 # some more aliases
 alias cal='cal -m'
 export FFOO_PRETTY=color
 
 # make green git bash trinket even cooler
-export GIT_PS1_SHOWDIRTYSTATE=true
-export GIT_PS1_SHOWUNTRACKEDFILES=true
-export GIT_DISABLED_COMMANDS="$HOME/.gittum/disabled-commands"
+GIT_PS1_SHOWDIRTYSTATE=true
+GIT_PS1_SHOWUNTRACKEDFILES=true
+GIT_DISABLED_COMMANDS="$HOME/.gittum/disabled-commands"
 
 # disable mounting things like SFTP to ~/.gvfs when accessed
 # via GIO (used by nautilus etc.)