updated 99problems: slice solution optimized -> tail recuisive and use one additional function
slice in 99problems: avoid constructing a list to be discarded
Merge branch 'master' of https://github.com/ocaml/ocaml.org
99problems: recover the original solution for slice
add stack.ml;
about.md: add content

Add content regarding Aims, Governance, and How to Contribute. Text
provided by Amir and slightly modified by Ashish. Partially addresses
about.md: add table of contents
Merge branch 'master' into about
about.md: add brief section on logos

Partially addresses #265.
Merge branch 'master' of github.com:zma/ocaml.org
Merge branch 'about'
mailing_lists.md: add French IRC channel
mailing_lists.md: add intro with info on other lists and forums
community/index.md: change link to mailing lists

Was to lists.ocaml.org, which only covers small set of all lists. Now
linking to main mailing lists page.
community/index.md: change Events to Meetings

Section links to Meetings page, and we refer to it as “meetings”
everywhere else.
mailing_lists.md: minor grammar fixes
About: say a word on the possibility to edit on Github
Typo correction
Merge pull request #384 from bluddy/patch-1

Typo correction
Added Esper to list of companies, removed mention of Skydeck (defunct),
updated Mr. Number.