[ticket/12956] Ensure the contact columns have been added before using them

PHPBB3-12956
[ticket/12950] Force the installer to use language=en

PHPBB3-12950
Merge remote-tracking branch 'github-dhruvgoel92/ticket/12950' into develop-ascraeus

* github-dhruvgoel92/ticket/12950:
  [ticket/12950] Force the installer to use language=en
Merge pull request #2858 from nickvergessen/ticket/12956

[ticket/12956] Ensure the contact columns have been added before using t...

* nickvergessen/ticket/12956:
  [ticket/12956] Ensure the contact columns have been added before using them