pidgin/pidgin

Stop automatically adding/remove conversations from the conversation manager

This was done to mimic the old conversations API and shouldn't be needed going
forward. However, since we can't create conversations right now, we're probably
missing some edge cases here.

Also make sure to keep a reference around on the conversation while removing to avoid use after frees.

Testing Done:
Trained with the turtles.

Reviewed at https://reviews.imfreedom.org/r/3049/
#include <winver.h>
VS_VERSION_INFO VERSIONINFO
FILEVERSION @PURPLE_MAJOR_VERSION@,@PURPLE_MINOR_VERSION@,@PURPLE_MICRO_VERSION@,0
PRODUCTVERSION @PURPLE_MAJOR_VERSION@,@PURPLE_MINOR_VERSION@,@PURPLE_MICRO_VERSION@,0
FILEFLAGSMASK 0
FILEFLAGS 0
FILEOS VOS__WINDOWS32
FILETYPE VFT_APP
FILESUBTYPE VFT2_UNKNOWN
BEGIN
BLOCK "StringFileInfo"
BEGIN
BLOCK "040904B0"
BEGIN
VALUE "CompanyName", "The Pidgin developer community"
VALUE "FileDescription", "Finch UI library"
VALUE "FileVersion", "@PURPLE_VERSION@"
VALUE "InternalName", "libfinch"
VALUE "LegalCopyright", "Copyright (C) 1998-2014 The Pidgin developer community (See the COPYRIGHT file in the source distribution)."
VALUE "OriginalFilename", "libfinch-@PURPLE_API_VERSION@.dll"
VALUE "ProductName", "Finch"
VALUE "ProductVersion", "@PURPLE_VERSION@"
END
END
BLOCK "VarFileInfo"
BEGIN
VALUE "Translation", 0x409, 1200
END
END