messages: Unify notation of "LDAP" in English translation

Replace ldap, Ldap by the standard notation LDAP in the English
translation. The German translation already uses the correct notation.

Signed-off-by: Stefan Weil <sw@weilnetz.de>
messages: Fix grammar in English translation

Signed-off-by: Stefan Weil <sw@weilnetz.de>
config: Fix some typos in comments

Signed-off-by: Stefan Weil <sw@weilnetz.de>
src: Fix some typos in comments

Signed-off-by: Stefan Weil <sw@weilnetz.de>
Merge pull request #177 from stweil/1.10.x

Typo fixes and text cleanups in comments