Testing sequence

1. Start kcharselect
    * Expectation: User presented with application default view - in my case, "European Alphabets / Basic Latin" - PASS
2. Focus the text box with the placeholder, "Enter a search term or character here"
    * Expectation: User is presented with carat, and can enter text - PASS
3. Type a search, e.g., "gamma"
    * Expectation: As user types past three letters, set of characters from the unicode spaces whose metadata match the search are placed into the character list below - PASS
4. Tap [backspace] until the field is empty
    * Expectation: As user removes letters, set of characters from the unicode spaces whose metadata match the search are placed into the character list below - PASS
    * Expectation: As user removes third-to-last letter, user is returned to the application default view - FAIL
    * Actual result: Character list remains in searched state
    * Expectation: As user removes last letter, placeholder is restored - FAIL
    * Actual result: Application exits; only output is `Segmentation fault (core dumped)`

Environment details:

    * Distribution: Ubuntu 16.04
    * uname: Linux 4.4.0-21-lowlatency
    * kcharselect --version: 1.12
    * kcharselect depndencies:
        * libc6:  2.23-0ubuntu3
        * libkf5configcore5:  5.18.0-0ubuntu1
        * libkf5configgui5:  5.18.0-0ubuntu1
        * libkf5configwidgets5:  5.18.0-0ubuntu1
        * libkf5coreaddons5:  5.18.0-0ubuntu1
        * libkf5i18n5:  5.18.0-0ubuntu1
        * libkf5widgetsaddons5:  5.18.0-0ubuntu1
        * libkf5xmlgui5:  5.18.0-0ubuntu1
        * libqt5core5a:  5.5.1+dfsg-16ubuntu7
        * libqt5gui5:  5.5.1+dfsg-16ubuntu7
        * libqt5gui5-gles: n/a
        * libqt5widgets5:  5.5.1+dfsg-16ubuntu7
        * libstdc++6:  5.3.1-14ubuntu2

Cursory look at core dump (attached):

	gdb `which kcharselect`
	GNU gdb (Ubuntu 7.11-0ubuntu1) 7.11
	Copyright (C) 2016 Free Software Foundation, Inc.
	License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
	This is free software: you are free to change and redistribute it.
	There is NO WARRANTY, to the extent permitted by law.  Type "show copying"
	and "show warranty" for details.
	This GDB was configured as "x86_64-linux-gnu".
	Type "show configuration" for configuration details.
	For bug reporting instructions, please see:
	<http://www.gnu.org/software/gdb/bugs/>.
	Find the GDB manual and other documentation resources online at:
	<http://www.gnu.org/software/gdb/documentation/>.
	For help, type "help".
	Type "apropos word" to search for commands related to "word"...
	Reading symbols from /usr/bin/kcharselect...(no debugging symbols found)...done.
	(gdb) core core
	[New LWP 13816]
	[New LWP 13817]
	[New LWP 13818]
	[New LWP 13819]
	[New LWP 13821]
	[New LWP 13820]
	[New LWP 13822]
	[Thread debugging using libthread_db enabled]
	Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
	Core was generated by `kcharselect'.
	Program terminated with signal SIGSEGV, Segmentation fault.
	#0  0x00007ff5e5a3d51d in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
	[Current thread is 1 (Thread 0x7ff5e6cb18c0 (LWP 13816))]

libQt5Widgets.so.5 belongs to Ubuntu package libqt5widgets5.  Without a trace it's not clear it's at fault.