Fix paragraph tightness

`state.tight` might be updated in the rules, so we should set it
after running rules, not before

lib/lexer_block.js

@@ -127,8 +127,6 @@ LexerBlock.prototype.tokenize = function (state, startLine, endLine) {
     if (state.tShift[line] < state.blkIndent) { break; }
     if (state.bqMarks[line] < state.bqLevel) { break; }
 
-    state.tight = !hasEmptyLines;
-
     // Try all possible rules.
     // On success, rule should:
     //
@@ -149,6 +147,10 @@ LexerBlock.prototype.tokenize = function (state, startLine, endLine) {
 
     line = state.line;
 
+    // set state.tight iff we had an empty line before current tag
+    // i.e. latest empty line should not count
+    state.tight = !hasEmptyLines;
+
     if (line < endLine && isEmpty(state, line)) {
       hasEmptyLines = true;
       line++;