[Core][File and Folder name][MAC only]: Slash in folder name is recognized incorrectly when drag a folder on OS into Brackets window.

[julieyuan]

Steps:

1. Launch Brackets.
2. New a folder with name has slash, for example: ///MNGD\JKHGF//HHH222 on OS.
3. Drag this folder into Brackets window.
4. New another folder with name only has forward slash, for example: 111///ASDF////222
5. Repeat step3.

Result: At step3, it will pop up an error opening dialog, but the folder name is inconsistent with the the name on OS.The forward slash is recognized as colon, and the backslash is recognized as forward slash. At step5, it will open the folder correctly, but the name displays incorrectly, the forward slash is recoginized as colon.

Expected: These folders with slash in their names should not be opened in Brackets.

ENV: MAC 10.8 English OS Build: 0.31.0-9163

Notes: This issue not reproduces in Win OS.

Snapshots: Please refer to snapshots for details:

[gruehle]

Reviewed, low priority to @RaymondLim