add touch support (#77)

* initial work on touch support

* add touch support to all objects

* add touch scrolling, fix scrollbar, fix appstore search

- when fireing an action, the action array may change. so the loop should break early as soon as an action is handled.
  this fixes the appstore search when pressing B.
- scrollbar no longer goes oob. fixes #76

currently, scrolling has no acceleration.

sphaira/source/ui/progress_box.cpp

@@ -119,7 +119,7 @@ auto ProgressBox::NewTransfer(const std::string& transfer)  -> ProgressBox& {
     return *this;
 }
 
-auto ProgressBox::UpdateTransfer(u64 offset, u64 size)  -> ProgressBox& {
+auto ProgressBox::UpdateTransfer(s64 offset, s64 size)  -> ProgressBox& {
     mutexLock(&m_mutex);
     m_size = size;
     m_offset = offset;