Fix almost all warnings in cinelerra/.

Not fixing dcraw undefined behavour issues and some obsolete API issues.
Fix memory leak in BC_TextBox::paste_selection()

The allocated string used to get the clipboard data is not released
after it is copied into BC_TextBox::text.  It should be deleted after
use.

This fixes Covertiy CID 58539.
Remove unused Timer::delay_duration member variable

The Timer member variable delay_duration is not used.  It might have
been used by Timer::delay() ealier, but this static method uses its own
local variable now.  Remove the unused member variable to reduce memory
footprint of the Timer class.
Fix overflow warnings in plugins dot.C and effecttv.C

Killed warning: large integer implicitly truncated to unsigned type [-Woverflow]
Use configured localedir and package instead of hard-coded

Locale files are found where they are installed
Merge branch 'warning-cinelerra-fixall-take2'
Fix new[]/delete mismatch in PackageRenderer::direct_frame_copy().

At the end of the PackageRenderer::direct_frame_copy() function memory
is allocated using new [], and released using delete.  This patch fixes
the mismatch.  The issue was reported by Pierre.