Update bashrc.rear

Better intro message when "rear shell" launches bash within ReaR.

usr/share/rear/lib/bashrc.rear

@@ -8,7 +8,7 @@ alias md='mkdir -p'
 alias which='type -p'
 alias rehash='hash -r'
 
-# very important for our scripts to work!
+# mandatory for our scripts to work
 shopt -s nullglob extglob
 
 eval "$REAR_EVAL" &>/dev/null
@@ -20,10 +20,11 @@ for script in $SHARE_DIR/lib/*functions.sh ; do source $script ; done
 source $SHARE_DIR/lib/progresssubsystem.nosh
 
 echo "
-WARNING! This is the interactive shell within $PRODUCT. It
-is intended for development and testing purposed only and
-comes without warranty. The typical usage scenario is to
-source scriptlets into this shell to test their behaviour.
+This is the interactive shell (bash) within $PRODUCT.
+It is intended for development and testing of $PRODUCT
+to find out how things behave within the $PRODUCT environment.
+For example you can call $PRODUCT specific functions
+or source $PRODUCT scripts to test their behaviour.
 
 SHARE_DIR=$SHARE_DIR BUILD_DIR=$BUILD_DIR
 "