* implement the first steps for the write to the server config ffiles

* web.config part and some cleanup

* implement htaccess generator

* complete htaccess code

* add en-GB language string and UI option

* apply xml changes

* fix validation rule and wrong variable names

* some coderstyle changes

* some more fixes

* improve language string about the error message

* alpha order language strings

* 2018 -> 2019 && .sys.ini vs .ini

* de-DE translation

* improve en-GB thanks @brianteeman

* seccond round of @yvesh fixes

* set php minimum back to 7.0

* add server software checks

* allow the plugin to be installed in 3.8 too

* array() vs [] and statucHeaderConfiguration global var and additional use calls

* date format

* adress issues raised by @SniperSister

* thanks @brianteeman

* add suggestions by @brianteeman thanks 👍

* catch the error and the success message is the default case

* the htacces gets lower priority else we have the headers two times

* phpcs

* fr-FR strings by @Sandra97 

* Typos corrected - Wikipedia links edited

* New strings added

* Update fr-FR.plg_system_httpheader.ini

* Update fr-FR.plg_system_httpheader.sys.ini

* Typo corrected

* Little improvements (#12)

* Bring consistency with other plugin translations (#11)

* undefined variable

* correct getServerConfigFilePath

* correct getServerConfigFilePath

* correct getServerConfigFile

* push server config file to the success message

* update fr-FR to use noopener and noreferrer

* add extra space for the csp headers after the ;

* Italian language file (#13)

* Italian language file

Italian language for the plugin.

* Update it-IT.plg_system_httpheader.sys.ini

Updated language file to match the new branch

* Rename it-IT.plg_system_httpheader.sys.ini to it-IT.plg_system_httpheader.ini

* Create it-IT.plg_system_httpheader.sys.ini

* noopener noreferrer

* use the same style for the translator mention

* pull of the updater file changes