UniSender Integration

Unisender 1.7.6

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1. Fix bug with wrong edit url.

Unisender 1.7.5

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1. Change api protocol to https

2. Added identification parametr for api connection

3. Fix several bugs in lang file

Unisender 1.7.4

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1. Fix bug with wrong subscribe urls

Unisender 1.7.3

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1. Added internal statistic

Unisender 1.7.2

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1. Fix bug on E-mail sending

2. Fix several bugs in code

Unisender 1.7.1

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1. Fix bugs in subscribers list.

2. Fix bugs with subscription for users.

3. Fix problems during install.

4. Fix bug with "double_optin".