New edits

- Validations in sign_in and sign_up 
(Even thought validations are not working in my copy of pickoneside, cuz last time it was interfering with some js file - check and let me know if it solves the problem, as i have increased the width of the forms. And i will fetch data after this)
- Added the Home navigation that you wanted.
- I am going to begin making pickoneside top navigation bar "responsive".. cheers..