Changed signal/slot connections to avoid override of accept() method

Fixed connections so that settings are applied when the OK or Apply
buttons are clicked.  The dialog closes only when the OK button is
clicked. The result code returned when calling exec() is also correct.

Change-Id: Ibc84998b6d43535f7f0f1a2fa1f5d9272b0b1028
Use fix-int64_t change from VisItBridge

Change-Id: I83c4ca5f9d94fcceade4763cef2684aaacdce85e
Remove duplicate tiff readers.

When opening tiff files, user was always prompted to choose between two
tiff readers. I think we need to cleanup image readers and image-series
readers, but that can happen later.

Change-Id: I25505b6f9546fe3699f7038250575044cbee0a77
!= was being used instead of == in conditional

With this operator, this conditional was checking for whether the
global proxy ID existed in a std::set that used to ensure uniqueness
of the proxy in the collection. Instead, it should check whether that
ID wasn't in the std::set.

Added test for this fix

Change-Id: I0a2b5bb614acff6bdc557ba9da7c1ef85c501691
Removed vtkMatplotlibUtilities class

It is no longer needed.

Change-Id: Ia60dfec4b394355e7eda848a19dd12c28a9d3a37
Update VTK to bring in opacity fix.

Change-Id: Ie0437119b65891b9eb065b6e4519ec07b4204f1f
Fix vtkSMTrace segfault when char* is NULL.

Handled by passing a None when char* is NULL.

Change-Id: I256c759a8f4a4b120b6ac042441e76afcf407256
Fix segfault seen in BUG #9808.

On certain platforms, the comparison operator is called for sorting with
same arguments. We skipped that case in our "assert". Fixed that.

Change-Id: I8fdc496d2b078878dca21eca64b8b8ce3547285a
Merge topic 'fix_apply_pqProxyWidgetDialog'

374911f3 Changed signal/slot connections to avoid override of accept() method
Merge topic 'fix_get_proxies'

645ac1ea != was being used instead of == in conditional
Merge topic 'fix-int64_t'

ebfe016d Use fix-int64_t change from VisItBridge
Merge topic 'remove_duplicate_tiff_readers'

f6dc4055 Fix segfault seen in BUG #9808.
e1b8c5d3 Fix vtkSMTrace segfault when char* is NULL.
f0999171 Update VTK to bring in opacity fix.
89d073e3 Remove duplicate tiff readers.
Merge topic 'remove_matplotlib_utilities'

777e72b5 Removed vtkMatplotlibUtilities class