ogma-cli: Re-order README's TOC to match order of contents. Refs #88.

The table of contents in the README lists C structs ahead of the ROS and FPrime
backends, but the order of sections in the file puts those backends first.

This commit updates the TOC to reflect the current order.

ogma-cli/README.md

@@ -46,9 +46,9 @@ verification framework that generates hard real-time C99 code.
 - [Usage](#usage)
   - [Language Transformations: FRET](#language-transformations-fret)
   - [cFS Application Generation](#cfs-application-generation)
-  - [Struct Interface Generation](#struct-interface-generation)
   - [ROS Application Generation](#ros-application-generation)
   - [F' Component Generation](#f-component-generation)
+  - [Struct Interface Generation](#struct-interface-generation)
 - [Contributions](#contributions)
 - [Acknowledgements](#acknowledgements)
 - [License](#license)