Fixes the error message when there is no items in a buffer (#9)

This commit fixes the error message when user tries to navigate the
buffer that doesn't contain items.

Author: aserebryakov

README.md

@@ -124,6 +124,7 @@ Changelog
 
 * Added items toggling in visual mode
 * Improves work with indentations of list items
+* Fixed the error when trying to navigate the buffer that doesn't contain items
 
 Credits
 -------

doc/vim-todo-lists.txt

@@ -1,4 +1,4 @@
-*vim-todo-lists.txt*    Version 0.2.0
+*vim-todo-lists.txt*    Version 0.3.0
 *vim-todo-lists*
 
 Plugin for TODO lists management.
@@ -156,6 +156,7 @@ SOFTWARE.
 
 * Added items toggling in visual mode
 * Improves work with indentations of list items
+* Fixed the error when trying to navigate the buffer that doesn't contain items
 
 ==============================================================================
 8. Credits                                                 *VimTodoListsCredits*

plugin/vim-todo-lists.vim

@@ -93,8 +93,8 @@ endfunction
 " Moves te cursor to the next item
 function! VimTodoListsGoToNextItem()
   normal! $
-  silent exec '/^\s*\[.\]'
-  silent exec 'noh'
+  silent! exec '/^\s*\[.\]'
+  silent! exec 'noh'
   normal! f[
   normal! l
 endfunction
@@ -103,8 +103,8 @@ endfunction
 " Moves te cursor to the previous item
 function! VimTodoListsGoToPreviousItem()
   normal! 0
-  silent exec '?^\s*\[.\]'
-  silent exec 'noh'
+  silent! exec '?^\s*\[.\]'
+  silent! exec 'noh'
   normal! f[
   normal! l
 endfunction