Support for contactId in email params

See merge request !10

Clarify variable name $email -> $toEmail

See merge request !7

fixes #5: Incorrect argument for tokenValues hook

Closes #5

See merge request !6

Code formatting and drop support for < 5.x

See merge request extensions/emailapi!4

upgrade_1004 and upgrade_1005 do not check if org.civicoop.civirules is installed

See merge request !2

Fix typo and missing email in status message.

See merge request !1

Execute CiviRules upgrade sql statements only if CiviRules is installed

Get contact and contribution tokens working

Fix for some bad behavior in issue #10

Fix tokens and remove exception

We're seeing behavior described in #10 , and this change fixes the issue for us.

Actually what's happening for us is that by using `array_merge()` here, tokens that are not in `$body_subject` are simply not appearing in `$tokens`. Issue #10 doesn't describe the issue in exactly that way, but there's some chance that indeed that's the situation.