Sequence parser: wait for RS on startup (fix #687)

Per-RFC7464.

tests/run

@@ -111,7 +111,6 @@ fi
 ## into tests/all.test
 
 cat > $d/expected <<EOF
-ignoring parse error: Potentially truncated top-level numeric value at line 1, column 2
 ignoring parse error: Truncated value at line 2, column 5
 ignoring parse error: Truncated value at line 2, column 25
 ignoring parse error: Truncated value at line 2, column 41
@@ -120,7 +119,6 @@ printf '1\0362 3\n[0,1\036[4,5]true"ab"{"c":4\036{}{"d":5,"e":6"\036false\n'|$VA
 cmp $d/out $d/expected
 
 cat > $d/expected <<EOF
-ignoring parse error: Potentially truncated top-level numeric value at line 1, column 2
 ignoring parse error: Truncated value at line 2, column 5
 ignoring parse error: Truncated value at line 2, column 25
 ignoring parse error: Truncated value at line 3, column 1
@@ -131,21 +129,21 @@ cmp $d/out $d/expected
 # Note that here jq sees no inputs at all but it still succeeds because
 # --seq ignores parse errors
 cat > $d/expected <<EOF
-ignoring parse error: Unfinished string at EOF at line 1, column 4
+ignoring parse error: Unfinished abandoned text at EOF at line 1, column 4
 EOF
 printf '"foo'|./jq -ce --seq . > $d/out 2>&1
 cmp $d/out $d/expected
 
 # Numeric values truncated by EOF are ignored
 cat > $d/expected <<EOF
-ignoring parse error: Potentially truncated top-level numeric value at EOF at line 1, column 1
+ignoring parse error: Unfinished abandoned text at EOF at line 1, column 1
 EOF
 printf '1'|./jq -ce --seq . > $d/out 2>&1
 cmp $d/out $d/expected
 
 cat > $d/expected <<EOF
 EOF
-printf '1\n'|./jq -ces --seq '. == [1]' >/dev/null 2> $d/out
+printf '1\n'|./jq -cen --seq '[inputs] == []' >/dev/null 2> $d/out
 cmp $d/out $d/expected
 
 ## Test streaming parser