Add initial and incomplete support for SIG{CONT,TSTP}

This is probably still not completely correct, e.g. can we gracefully
handle the case where `/' is pressed and some input for the search
was entered?

diff --git a/common.h b/common.h
index 675260c..b4e06c2 100644
--- a/common.h
+++ b/common.h
@@ -35,4 +35,6 @@ char *uiprompt(char *fmt, ...);
 Item *uiselectitem(Item *entry);
 void uisetup(void);
 void uisigwinch(int signal);
+void uisigcont(int signal);
+void uisigtstp(int signal);
 void uistatus(char *fmt, ...);
diff --git a/sacc.c b/sacc.c
index 1ed1d1c..60e62ca 100644
--- a/sacc.c
+++ b/sacc.c
@@ -965,6 +965,10 @@ setup(void)
 		uisetup();
 		sa.sa_handler = uisigwinch;
 		sigaction(SIGWINCH, &sa, NULL);
+		sa.sa_handler = uisigcont;
+		sigaction(SIGCONT, &sa, NULL);
+		sa.sa_handler = uisigtstp;
+		sigaction(SIGTSTP, &sa, NULL);
 	}
 }
 
diff --git a/ui_ti.c b/ui_ti.c
index ae11338..c324043 100644
--- a/ui_ti.c
+++ b/ui_ti.c
@@ -1,3 +1,4 @@
+#include <signal.h>
 #include <stdarg.h>
 #include <stdio.h>
 #include <stdlib.h>
@@ -554,8 +555,7 @@ uisigwinch(int signal)
 {
 	Dir *dir;
 
-	setupterm(NULL, 1, NULL);
-	putp(tparm(change_scroll_region, 0, lines-2, 0, 0, 0, 0, 0, 0, 0));
+	uisetup();
 
 	if (!curentry || !(dir = curentry->dat))
 		return;
@@ -565,3 +565,19 @@ uisigwinch(int signal)
 
 	uidisplay(curentry);
 }
+
+void
+uisigcont(int signal)
+{
+
+	uicleanup();
+	uisigwinch(signal);
+}
+
+void
+uisigtstp(int signal)
+{
+
+	uicleanup();
+	kill(getpid(), SIGSTOP);
+}
diff --git a/ui_txt.c b/ui_txt.c
index 3b9d964..d7d868f 100644
--- a/ui_txt.c
+++ b/ui_txt.c
@@ -1,10 +1,12 @@
 #include <ctype.h>
 #include <errno.h>
+#include <signal.h>
 #include <stdarg.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 #include <termios.h>
+#include <unistd.h>
 #include <sys/ioctl.h>
 #include <sys/types.h>
 
@@ -336,3 +338,17 @@ uisigwinch(int signal)
 	printstatus(curentry, cmd);
 	fflush(stdout);
 }
+
+void
+uisigcont(int signal)
+{
+
+	uisigwinch(signal);
+}
+
+void
+uisigtstp(int signal)
+{
+
+	kill(getpid(), SIGSTOP);
+}