Add islog internal key to quickly is the resolve file concern the logger itself.
Add the rversion internal field. This field will be used to know the previous
version of the resolve file and possibly make an
automatic migration of the db to the new format.

At write time:
  - Add the whole sa to the new cdb field named sa instead of storing the key one by one.
  - Store uniquely the uint of the key instead of appending a string.

At read time:
  - Do not build again the sa looking for the cdb value but read the whole sa instead.
  - Do not use extra HEAP memory allocation.
At modification time:
  - Sanitize the resolve by writting the sa from scratch.
  - Use /tmp directory as temporary cdb file.
Replace resolve_find_cdb by the resolve_get_key and resolve_get_sa function.
Replace service_resolve_copy by service_resolve_sanitize.

Rename TimeoutKill to TimeoutStart.
Rename TimeoutFinish to TimeoutStop.
Remove TimeoutUp and TimeoutDown key.
To avoid confusion and mistake, oneshot and classic service use now
the same key name to declare the timeout to use.
TimeoutStart and TimeoutStop are clearer than TimeoutKill and TimeoutFinish.
66 is sufficiently smart to name the file correctly for s6-supervise
whick look for the timeout-kill and timeout-finish file.

Key name now begin with a capital letters instead of using the '@' character.
Also, '-' character are removed from  a composite name.
This is introduce the very first change of the key field.
Some simplications and changes to the key name will be made.
Add the  get_enum_list() function.

This is a necessary review for new coming section.
Each table are now used separately.
More lignes of code but a shorter execution and a
easier manner to deal with API to integrate new section.

This reverts commit 87bd69c6.