BUG: Multiple whitespace was condensed, CR/LF not turned to space.

Missing quoting inside cleaninput() condensed multiple subsequent spaces into a single space, even when the user took pains to preserve whitespace by properly quoting the task in the shell.
The 'tr' command completely removed CR and LF characters instead of replacing them with a single space.
Add test cases for the whitespace handling to the add, append, prepend and replace actions.

tests/t1000-addlist.sh

@@ -77,4 +77,37 @@ TODO: 5 added.
 TODO: 5 of 5 tasks shown
 EOF
 
+#
+# Advanced add
+#
+
+cat /dev/null > todo.txt
+test_todo_session 'add with spaces' <<EOF
+>>> todo.sh add "notice the   three   spaces"
+1 notice the   three   spaces
+TODO: 1 added.
+
+>>> todo.sh add notice how the   spaces    get lost
+2 notice how the spaces get lost
+TODO: 2 added.
+
+>>> todo.sh list
+2 notice how the spaces get lost
+1 notice the   three   spaces
+--
+TODO: 2 of 2 tasks shown
+EOF
+
+cat /dev/null > todo.txt
+test_todo_session 'add with CR' <<EOF
+>>> todo.sh add "smell the
+Carriage Return"
+1 smell the Carriage Return
+TODO: 1 added.
+
+>>> todo.sh list
+1 smell the Carriage Return
+--
+TODO: 1 of 1 tasks shown
+EOF
 

tests/t1100-replace.sh

@@ -89,6 +89,14 @@ TODO: Replaced task with:
 1 thrash the hay & thrash the wheat
 EOF
 
+echo 'jump on hay' > todo.txt
+test_todo_session 'replace with spaces' <<EOF
+>>> todo.sh replace 1 "notice the   three   spaces"
+1 jump on hay
+TODO: Replaced task with:
+1 notice the   three   spaces
+EOF
+
 cat > todo.txt <<EOF
 smell the cows
 grow some corn

tests/t1400-prepend.sh

@@ -57,6 +57,12 @@ test_todo_session 'prepend with &' <<EOF
 3 no running & jumping now stop
 EOF
 
+echo 'jump on hay' > todo.txt
+test_todo_session 'prepend with spaces' <<EOF
+>>> todo.sh prepend 1 "notice the   three   spaces and"
+1 notice the   three   spaces and jump on hay
+EOF
+
 cat > todo.txt <<EOF
 smell the cows
 grow some corn

tests/t1600-append.sh

@@ -43,6 +43,12 @@ test_todo_session 'basic append with &' <<EOF
 TODO: 1 of 1 tasks shown
 EOF
 
+echo 'jump on hay' > todo.txt
+test_todo_session 'append with spaces' <<EOF
+>>> todo.sh append 1 "and notice the   three   spaces"
+1 jump on hay and notice the   three   spaces
+EOF
+
 cat > todo.txt <<EOF
 smell the cows
 grow some corn