[meta] ABP for IE 1.1 post-release cleanup

[trev]

Background

With ​https://hg.adblockplus.org/adblockplusie/rev/b7c285b78846 we released ABP for IE in version 1.1. We now need to do some cleanup.

What to change

Do some post-release cleanup of ABP for IE 1.1 according to the following issues:

Ticket	Status	Resolution	Summary	Owner
#59	closed	fixed	[ABP IE 1.1 cleanup] Make url a parameter to Updater::Update(), get rid of Updater::SetUrl()	fhd
#60	closed	fixed	[ABP IE 1.1 cleanup] Remove CPluginSettings::m_subscriptions member
#61	closed	fixed	[ABP IE 1.1 cleanup] Parameter type of FilterLoader() function should be LPVOID
#62	closed	fixed	[ABP IE 1.1 cleanup] Use better names for local FilterLoader() variables
#63	closed	fixed	[ABP IE 1.1 cleanup] Reduce indentation level in CPluginTabBase::InjectABP()
#64	closed	fixed	[ABP IE 1.1 cleanup] Replace tabs by spaces in ieFirstRun.js
#65	closed	fixed	[ABP IE 1.1 cleanup] Fix the approach used by ieFirstRun.js	oleksandr
#66	closed	fixed	[ABP IE 1.1 cleanup] Remove PROC_GET_APP_LOCALE constant
#67	closed	fixed	[ABP IE 1.1 cleanup] Use MessageBoxW() explicitly in engine/Main.cpp
#69	closed	fixed	[ABP IE 1.1 cleanup] Simplify plugin enabling/disabling
#70	closed	fixed	[ABP IE 1.1 cleanup] Fix x64 warnings in ToUtf8String(), ToUtf16String(), GetDllDir(), Communication::Pipe::WriteMessage(): size_t needs to be converted to DWORD explicitly.	fhd
#71	closed	fixed	[ABP IE 1.1 cleanup] Fix x64 warning in OutputBuffer::WriteString(): size_t needs to be converted to SizeType explicitly.t	fhd
#72	closed	fixed	[ABP IE 1.1 cleanup] Make sure that it isn't possible to start two update checks in parallel.
#75	closed	fixed	[ABP IE 1.1 cleanup] Make sure update requests are using gzip compression
#76	closed	fixed	[ABP IE 1.1 cleanup] Check the 4oD player not loading error:

[philll]

The assigned state will be dropped by #403