Fix useS snippet in UltiSnips/javascript_react
Fix useS snippet in UltiSnips/javascript_react

Previously, the .title() function was used to capitalize the first item.
However, this function doesn't maintain the capitalization of letters in
the middle. Therefore, a custom function was created to effectively
convert camelCase to PascalCase.

phatograph/vim-snippets,honza/vim-snippets,honza/vim-snippets,adam-e-trepanier/vim-snippets,adam-e-trepanier/vim-snippets,craigp/vim-snippets,craigp/vim-snippets,kevinkirkup/vim-snippets,phatograph/vim-snippets,kevinkirkup/vim-snippets