update thunderbird to 45.7.1

https://www.mozilla.org/en-US/thunderbird/45.7.0/releasenotes/
https://www.mozilla.org/en-US/thunderbird/45.7.1/releasenotes/

After changes in packaging in ports r428672, profiles using lightning
will have to be recreated.

PR: 216584
Approved by: jbeich (maintainer), rene (mentor, implicit)
MFH: 2017Q1
Security: e60169c4-aa86-46b0-8ae2-0d81f683df09 e60169c4-aa86-46b0-8ae2-0d81f683df09