Improve error messages to show problematic position in the filter (#3292)

This commit improves the parser and compiler error messages, making
it more easier to understand where in the filter the problem is.
Like modern compilers, jq will show the line in the filter where the
error occurred, will display squiggly line under the invalid token.

tests/shtest

@@ -634,6 +634,29 @@ EOF
   fi
 fi
 
+# Test syntax error messages of multiline filter (we can't test in jq.test)
+if $VALGRIND $Q $JQ -n '[
+  try if .
+         then 1
+         else 2
+  catch ]' > $d/out 2>&1; then
+  echo 'syntax error not detected'
+  exit 1
+fi
+cat > $d/expected <<EOF
+jq: error: syntax error, unexpected catch, expecting end or '|' or ',' at <top-level>, line 5, column 3:
+      catch ]
+      ^^^^^
+jq: error: Possibly unterminated 'if' statement at <top-level>, line 2, column 7:
+      try if .
+          ^^^^
+jq: error: Possibly unterminated 'try' statement at <top-level>, line 2, column 3:
+      try if .
+      ^^^^^^^^
+jq: 3 compile errors
+EOF
+diff $d/out $d/expected
+
 # Comments!
 if ! x=$($JQ -n '123 # comment') || [ "$x" != 123 ]; then
   echo 'comment did not work'