releases scheduling

[Thomas Monjalon <thomas.monjalon@6wind.com>]

Hi all,

We need to define the deadlines for the next releases.
During 2015, we were doing a release every 4 months.
If we keep the same pace, the next releases would be:
	2.3: end of March
	2.4: end of July
	2.5: end of November

However, things move fast and it may be a bit long to wait 4 months for
a feature. That's why I suggest to progressively shorten release terms:
	2.3: end of March
	2.4: mid July
	2.5: end of October
and continue with a release every 3 months:
	2.6: end of January
	2.7: end of April
	2.8: end of July
This planning would preserve some of the major holiday periods
(February, May, August, December).

The first period, for the first submission of a feature, was 2 months long.
Then we had 2 other months to discuss, merge and fix.
We should shorten only the first period.

Anyway, the next deadlines should be unchanged:
	- January 31: end of first submission phase
	- March 31: release 2.3

Opinions are welcome.