Fix transcript's first line skipping
Fix transcript's first line skipping

- LEARNER-242
We are using subtitleConvert library's FormatSRT class to parse our
transcript files which by default expects the index of captions within
the file to be starting from 1.
Our transcript files start their captions' index from 0, so, the library
has been modified and the jar updated to support our captions properly.
Previously due to the index issue, we were skipping the first caption in
our transcript files.
Library's GitHub link: https://github.com/JDaren/subtitleConverter

edx/edx-app-android,edx/edx-app-android,edx/edx-app-android,edx/edx-app-android,edx/edx-app-android,edx/edx-app-android