Geomon data fetching - Add "validity" column in position table

[guillaumeVolery]

Current behavior:

If a position .pos file does not contain any position sample, or if there isn't any sample having Q=1, the position file is ignored and not stored in the database.

The following messages are printed on the console by the fetching function:

• No .pos file found in GM_BASE_0002/160211_16 -> Operation aborted
• No position data in GM_BASE_0002/160722_14/160722_144219_00002_rxNVS_GPS4.pos -> Operation aborted
• No position with Q = 1 in file GM_BASE_0002/160726_18/160726_182147_00001_rxNVS_GPS4.pos -> Operation aborted

New requirement:

All position files must be stored in the files table. Moreover, a new validity column (enum type) shall be added to the positions table in order to differentiate the following enumeration of cases:

1. valid -> .pos file contains enough position samples with Q = 1.
2. no_samples -> .pos file doesn't contain any position sample (empty).
3. too_less_samples -> .pos file doesn't contain enough (< 12) samples with Q = 1.

[guillaumeVolery]

Column added in commit 4262642

Validity management to be done.

[guillaumeVolery]

According @VincentSchlageter, validity column to be removed.