Fix error when adding a new account when installation path is greater than 245 characters

Steps to reproduce:
1. Create folder structure as below:
“C:\AAAAAAAAA... (100 chars)\BBBBBB... (100Chars)\CCCCC...” (>45 chars)
2. Install Drive client. While setting account, select the above folder “\CCCCC...” as nuxeo-drive setup folder
3. Try to login

Expected Result: Login should be successful
Actual Result: Login fails, stating that cannot able to find the folder

Error from the logs

2017-01-05 16:36:09,200 2952 2956 ERROR    nxdrive.wui.settings [Error 3] The system cannot find the path specified: u'C:\\AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA\\BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB\\CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC\\.caseTest_19d9bc'