id,node_id,number,state,locked,title,user,body,created_at,updated_at,closed_at,merged_at,merge_commit_sha,assignee,milestone,draft,head,base,author_association,repo,url,merged_by,auto_merge
313007483,MDExOlB1bGxSZXF1ZXN0MzEzMDA3NDgz,56,closed,0,Escape the table name in populate_fts and search.,49260,"The table names weren't escaped using double quotes in the populate_fts method. 

Reproducible case: 
```
>>> import sqlite_utils
>>> db = sqlite_utils.Database(""abc.db"")
>>> db[""http://example.com""].insert_all([
...     {""id"": 1, ""age"": 4, ""name"": ""Cleo""},
...     {""id"": 2, ""age"": 2, ""name"": ""Pancakes""}
... ], pk=""id"")
<Table http://example.com (id, age, name)>
>>> db[""http://example.com""].enable_fts([""name""])
Traceback (most recent call last):
  File ""<input>"", line 1, in <module>
    db[""http://example.com""].enable_fts([""name""])
  File ""/home/amjith/.virtualenvs/itsysearch/lib/python3.7/site-packages/sqlite_utils/db.py"", l
ine 705, in enable_fts
    self.populate_fts(columns)
  File ""/home/amjith/.virtualenvs/itsysearch/lib/python3.7/site-packages/sqlite_utils/db.py"", l
ine 715, in populate_fts
    self.db.conn.executescript(sql)
sqlite3.OperationalError: unrecognized token: "":""
>>> 
```",2019-09-01T06:29:05Z,2019-09-02T17:23:21Z,2019-09-02T17:23:21Z,,79852e97ecb69b88da87da0cba2a55887cf83bda,,,0,83ca4c802f5d5102e73ff366e61514ded81dc7a1,cb70f7d10996b844154bf3da88779dd1f65590bc,CONTRIBUTOR,140912432,https://github.com/simonw/sqlite-utils/pull/56,,