Fix regressions in buffer settings initialization (#2035)
Fix regressions in buffer settings initialization (#2035)

Fix regressions after ba98b55:

- Unable to override filetype autodetection by setting a specific filetype
  for specific files, i.e. this doesn't work:

    "*.h": {
        "filetype": "c++"
    },

- Unable to enable/disable syntax highlighting for specific files,
  i.e. this doesn't work:

    "*.c": {
        "syntax": false
    },

- "readonly" setting doesn't work (neither global nor per-filetype).
zyedidia/micro,zyedidia/micro