Remove original getFile, getFileContent, and getFileJson and replace with getFile (which used to be getFileContent.. shortened now for convenience). Also remove unused getSubdirectories functions.
Existing solution uses HTML bodies for PR descriptions, as that was the easiest way to get consistency between GitHub and GitLab. However, VSTS supports only markdown so we needed to refactor how this is done. Now, GitHub PR bodies uses only minimal HTML (for summary/details) while GitLab PR bodies are converted to HTML using GitHub flavoured markdown for maximum compatibility. VSTS will be able to strip out the minimal markdown.
Closes#1018
This refactor means that createPr now takes `labels` as a new parameter so that the GitLab API can include them with the MR creation request, so save one API call. This also fixes#985 as a result.
