Parser: fix IDLE parsing

Dovecot might answer DONE with some statistics:

  IDLE OK Idle completed (0.001 + 0.093 + 0.092 secs).

The plus character passes RE_PRECEDING which leads to dead end
code-wise.

lib/Parser.js

@@ -11,7 +11,7 @@ var CH_LF = 10,
     LITPLACEHOLDER = String.fromCharCode(0),
     EMPTY_READCB = function(n) {},
     RE_INTEGER = /^\d+$/,
-    RE_PRECEDING = /^(?:(?:\*|A\d+) )|\+ ?/,
+    RE_PRECEDING = /^(?:\* |A\d+ |\+ ?)/,
     RE_BODYLITERAL = /BODY\[(.*)\] \{(\d+)\}$/i,
     RE_BODYINLINEKEY = /^BODY\[(.*)\]$/i,
     RE_SEQNO = /^\* (\d+)/,

test/test-parser.js

@@ -20,6 +20,10 @@ var CR = '\r', LF = '\n', CRLF = CR + LF;
     expected: [ 'IDLE OK IDLE terminated' ],
     what: 'Unknown line'
   },
+  { source: ['IDLE OK Idle completed (0.002 + 1.783 + 1.783 secs).', CRLF],
+    expected: [ 'IDLE OK Idle completed (0.002 + 1.783 + 1.783 secs).' ],
+    what: 'Unknown line with + char'
+  },
   { source: ['+ idling', CRLF],
     expected: [ { textCode: undefined,
                   text: 'idling'