Add Ecuador phone number validator

[mmena1]

This will add Ecuador phone number validation according to https://en.wikipedia.org/wiki/Telephone_numbers_in_Ecuador .
Closes #1186

[profnandaa]

LGTM. Thanks for your contrib! 🎉

[tux-tn]

@mrcrow85 according to ITU document about ecudator National Numbering Plans 9 digits number are only valid if the first digit is 9

• +593 987654321 is valid
• +593 287654321 is not valid (New network code always starts with 9)
• +591 912345678 is not valid (New network code is between 92 and 99)
  Can you confirm that?

[mmena1]

@mrcrow85 according to ITU document about ecudator National Numbering Plans 9 digits number are only valid if the first digit is 9

* +593 987654321 is valid

* +593 287654321 is not valid (New network code always starts with 9)

* +591 912345678 is not valid (New network code is between 92 and 99)
  Can you confirm that?

@tux-tn Oh, good catch! You are right, 9 digits numbers are only valid if the first digit is 9. As for the network code between 92 and 99, I read the legal resolution (which is in Spanish) which states that 0 and 1 are reserved numbers so 90 and 91 are invalid.

I will open an issue to address this followed by a PR to fix it.