Fix: Checking of a Valid URL or not

[dipesh23-apt]

• Are you fixing a bug or providing a failing unit test to demonstrate a bug?
  Yes, For checking a valid URL

• How do you reproduce it?
  By updating the regular expression format for the URL, by correcting the misplaced brackets and updating the * character to
  '+'.The * char in regular expression mean the * means "0 or more occurrences of the preceding item" and + char means "1 or
  more occurrences of the preceding item"
  Also there was a misplaced bracket of the form: ( (exp1... ) OR exp2)....
  instead it should have been of the form: ( (exp1...) ) OR (exp2....)
  The * specified after the form (.[a-zA-Z])* means it can have nil (.com/.eu) but updating it to '+' ensures (.com/.in/.xyz) be
  specified in the url to make it a valid url

• What was the previous behavior?
  Earlier it used to return true for http://abcd or xyz/qw
  which infact is not a valid URL as the domain name is not specified(.com/.eu/.in should be in the URL)
  which in turn makes the 'govalidator package' work similar to the net/url package with a bug.

• What is the current behavior?
  After modifying it, it returns false for http://abcd or wxe/123 or nmhih
  and in turn returns true for http://abcd.eu or xyz.ab or jkl.com

• Explain why the changes are necessary
  To check for a valid URL, there are two packages net/url and the govalidator package.But if this package does not return the
  correct output, there is no difference between the faulty package(net/url) and this one.
  So to be at a higher level and simplify the complexities of the user this commit needs to be merged.Also in various projects
  the checking of a valid URL is a crucial part, hence forth moving forward.

[sergeyglazyrindev]

Hello guys!
I forked this package cause owner disappeared. Hope, he will be back, but it would be easier to merge these changes back if he is back
Link to my repo: create issue there and we'll discuss it.