Use `env` wherever `preconfigopts` is used to set environmental vars

{bio}[intel/2016a] ncbi-vdb v2.5.8-1

{tools}[intel/2016a] SCOOP 0.7.1.1 w/ Python 2.7.11 (REVIEW)

Use `env` wherever `preinstallopts` is used to set env. vars

{bio}[intel/2016a] NGS v1.2.3

{bio} [foss-2015b,2016a] BEDTools-2.25.0

Without `env`, we are relying on a syntactical feature of Bourne-type
shells; the `env` utility guarantees that the command-line will continue
to work even with other shells (e.g., `tcsh`).

{lang}[dummy/dummy] Java v1.8.0_77

{system}[intel/2016a] file 5.25 + enhance sanity check (REVIEW)

{lang}[intel/2016a] numba 0.24.0 w/ Python 2.7.11 & 3.5.1 (REVIEW)

{devel}[dummy/] ant v1.9.6

{vis}[foss/2016a] Tk v8.6.4

{tools}[dummy/dummy] EasyBuild v2.7.0

New TAMkin easyconfig

bump version to 2.7.0 and update release notes

fix perl extensions download urls