Replaced `typeof` with `__typeof__` in `OnePasswordExtension.m`

This should resolve #124.

**Note to self:** Once this PR is merged we need to "cherrypick" the changes to the `add-low-level-api` branch
Merge pull request #125 from AgileBits/task/fix-typeofs

Replaced `typeof` with `__typeof__` in `OnePasswordExtension.m`
Fix clang warning about trailing semicolons.

Warning shows up with -Wsemicolon-before-method-body enabled.
Fix clang warning about shadowing local variables.

Warning shows up with -Wshadow enabled.
Merge pull request #113 from tijoinc/fix-clang-warnings

Fix Clang Warnings
Fixed brace style in OnePasswordExtension.m
Merge pull request #126 from AgileBits/task/fixed-brace-style

Fixed brace style in OnePasswordExtension.m
Merge branch 'master' into bugfix/fix-crash-when-the-extension-is-called-before-the-webview-is-fully-loaded

Conflicts:
	OnePasswordExtension.m