Added to prevent an exception described below on iOS7

Fatal Exception: NSInvalidArgumentException
*** -[NSProxy doesNotRecognizeSelector:numberOfSectionsInTableView:]
called!

Thread : Fatal Exception: NSInvalidArgumentException
0  CoreFoundation                 0x2e0c3e83 __exceptionPreprocess + 130
1  libobjc.A.dylib                0x3886a6c7 objc_exception_throw + 38
2  CoreFoundation                 0x2e0c3dc5 -[NSException
initWithCoder:]
3  Foundation                     0x2ea9bd01 -[NSProxy
doesNotRecognizeSelector:] + 68
4  CoreFoundation                 0x2e0c60af ___forwarding___ + 706
5  CoreFoundation                 0x2e014dc8 _CF_forwarding_prep_0 + 24
6  UIKit                          0x3091b189
-[UITableViewRowData(UITableViewRowDataPrivate) _updateNumSections] + 80
7  UIKit                          0x3091b0d1 -[UITableViewRowData
invalidateAllSections] + 72
8  UIKit                          0x3091ae6f -[UITableView
_updateRowData] + 194
9  UIKit                          0x3091ecb3 -[UITableView
noteNumberOfRowsChanged] + 94
10 UIKit                          0x3091e8cb -[UITableView reloadData]
+ 794
11 BriefcaseRD                    0x00047eed -[IBAFormViewController
viewWillAppear:] (IBAFormViewController.m:110)
12 UIKit                          0x308626ff -[UIViewController
_setViewAppearState:isAnimating:] + 346
13 UIKit                          0x308543c7 -[UIView(Hierarchy)
_willMoveToWindow:withAncestorView:] + 546
14 UIKit                          0x30846d75 __85-[UIView(Hierarchy)
_makeSubtreePerformSelector:withObject:withObject:copySublayers:]_block_
invoke + 76
15 UIKit                          0x30846ca3 -[UIView(Hierarchy)
_makeSubtreePerformSelector:withObject:withObject:copySublayers:] + 378
16 UIKit                          0x30846d95 __85-[UIView(Hierarchy)
_makeSubtreePerformSelector:withObject:withObject:copySublayers:]_block_
invoke + 108
17 UIKit                          0x30846ca3 -[UIView(Hierarchy)
_makeSubtreePerformSelector:withObject:withObject:copySublayers:] + 378
18 UIKit                          0x30846d95 __85-[UIView(Hierarchy)
_makeSubtreePerformSelector:withObject:withObject:copySublayers:]_block_
invoke + 108
19 UIKit                          0x30846ca3 -[UIView(Hierarchy)
_makeSubtreePerformSelector:withObject:withObject:copySublayers:] + 378
20 UIKit                          0x30853b9b -[UIView(Internal)
_addSubview:positioned:relativeTo:] + 418
21 UIKit                          0x308539f3 -[UIView(Hierarchy)
addSubview:] + 30
22 UIKit                          0x30935573 -[UITransitionView
transition:fromView:toView:removeFromView:] + 978
23 UIKit                          0x30935187
-[UIViewControllerBuiltinTransitionViewAnimator animateTransition:] +
450
24 UIKit                          0x30934bf1 __101-[UIWindowController
transition:fromViewController:toViewController:target:didEndSelector:ani
mation:]_block_invoke_2 + 1272
25 UIKit                          0x308c8781
_applyBlockToCFArrayCopiedToStack + 316
26 UIKit                          0x308407bb _afterCACommitHandler + 430
27 CoreFoundation                 0x2e08ef69
__CFRUNLOOP_IS_CALLING_OUT_TO_AN_OBSERVER_CALLBACK_FUNCTION__ + 20
28 CoreFoundation                 0x2e08c8f7 __CFRunLoopDoObservers +
286
29 CoreFoundation                 0x2e08cc43 __CFRunLoopRun + 738
30 CoreFoundation                 0x2dff7471 CFRunLoopRunSpecific + 524
31 CoreFoundation                 0x2dff7253 CFRunLoopRunInMode + 106
32 GraphicsServices               0x32d052eb GSEventRunModal + 138
33 UIKit                          0x308ac845 UIApplicationMain + 1136
34 BriefcaseRD                    0x000aee35 main (main.m:44)
35 libdyld.dylib                  0x38d63ab7 start + 2