All APIs returning star identifiers should return user-preferred alias

[rickyegeland]

Currently APIs returning stars return the canonical star name, which is set by SIMBAD. Users must build a list of names of their preferred alias (e.g. HD number). For example:

    # Fetch Cycle Data from sunstardb
    result = db.fetch_data_table('Baliunas1995', ['S_mean', 'activity_class', 'Pcyc', 'Pcyc2'], meta={'Pcyc':'FAPGrade'}, nulls=True)

    # Add an HD number column
    hds = []
    hdnums = []
    for star in result['star']:
        if star == 'Sun':
            hd = 'Sun'
            num = 0
        else:
            hd = db.fetch_star_alias(name=star, type='HD')
            num = int(re.match('^HD (\d+)', hd).group(1))
        hds.append(hd)
        hdnums.append(num)
    result['HD'] = hds
    result['Sort'] = hdnums

(Here the 'Sort' column allows the astropy.table.Table to sort the HD numbers in numerical, not lexical, order.)

Instead the user should be able to specify a list of preferred alias types. API example:

    # Fetch Cycle Data from sunstardb
    result = db.fetch_data_table('Baliunas1995', ['S_mean', 'activity_class', 'Pcyc', 'Pcyc2'], meta={'Pcyc':'FAPGrade'}, nulls=True, star_alias=['HD', 'GJ'])

If aliases are not available, the default can be the canonical identifier (star.name in the DB)