[pvr] fix open add timer dialog in timer window

After changing the special item 'Add timer...' to be a folder (to always
stay on top of the list) the path comparison fails, because the path now
ends with a slash.
StringUtils::FormatV: optimization: reduce default allocation size to 512 bytes as most formatted strings are small, replace malloc/realloc with simpler malloc/free
[win32] StringUtils::FormatV: use exact size on Win32 instead of doubling
binary addons: allow downloading addons as source packages instead of git repositories
Includes: Replace includes with "sub-includes" if possible.
Includes: Remove unnecessary includes.
Merge pull request #5041 from Karlson2k/FormatV_upd_01

StringUtils::FormatV: optimize, use exact size on Win32 instead of doubling
Merge pull request #5156 from xhaggi/pvr-fix-open-add-timer-dialog

[pvr] fix open add timer dialog in timer window
Merge pull request #3880 from ace20022/includes_1

Cleanup some includes
Merge pull request #5160 from Montellese/binary_addons_from_packages

binary addons: allow downloading addons as source packages instead of git repositories
Merge branch 'master' of https://github.com/xbmc/xbmc