Add ebuild for libtrevent

+# ChangeLog for dev-libs/libtrevent
+# Copyright 2016 Georg Hopp; Distributed under the GPL v3
+
+*libtrevent-1.0.0 (12 Apr 2016)
+
+  12 Apr 2016; Georg Hopp <georg@steffers.org> metadata.xml,
+  libtrevent-1.0.0.ebuild :
+    Initial import.

+DIST libtrevent-1.0.0.tar.gz 428393 SHA256 d0a8e0c79f4a77580ee119aead5542622561e97551209f1fec65c053ef6a35d7 SHA512 68f82e7ac6d43e866b4990111f14e6d674df227fd949ba9a0c39f8a0be1e6435cbed0481af0300667e401afe1230173949bd4d155750d4b4ca1285b8cdf3a781 WHIRLPOOL 6d8f9dbf8c06fde4740b4f6dc261ef5b81c959e74721e0a7f4452bf18868c073a1923b9d8545999bbcadef6e9c5699aaed23f62200d30c11e5097d8e44d0d638
+EBUILD libtrevent-1.0.0.ebuild 461 SHA256 ccfacd87919c955244527f7ca96c689bc1855f0bb454c370c736e9c19bc7db1d SHA512 c42d57dce2c3f73fd9d727e04c8ac072efe029e7320d99b86afbe411fbf4e407c68c256532ac83f81a8b9a39bec4f34d7dc0cb9251f80056a2ff7aac4a788edd WHIRLPOOL 5f3af99beead1642878d069088304f4d2f6e2b52ce1206584fe5a557a88a0a00ea1da7d6b6729d41c6237fba3b42b58e85e43c2fa9ac1142e13ea701357fad79
+MISC ChangeLog 237 SHA256 821e37721bc51571fe98f8a47a6a6d034cee22625cb88e047ca8979699f9af28 SHA512 7b51c8ef5a80fd8d06127c343896d88509a3126518dfc30c33ae3f7377f4785e0c0385f0a54480251ea104cecf2f0fbe98dcca3ee72a3b6d81f55537016c8c32 WHIRLPOOL 03a027674660791a5feb7fa1d72cf67af3bab42916f0e2026bab6b191556e6227023b355c9ee7dd057d1fd404fb88adba9f544cd8d64682c67e340dc6669a306
+MISC metadata.xml 351 SHA256 5ea5ee55de55e5b06466115b9c28c25d6660dc90b19b90d855fb5f698bb58464 SHA512 7156e6e6e9e80231d2352d4746776a1d69b6f2b52508229bfae1284794305c0c41244478f214ffb189b76ea0026b759456e044fa6fb1b9cce213a16b4d0f346c WHIRLPOOL 588ca82e3537415448346eb644d8e2a811113bb6b491775f0e3d28dfd2639a327cb5e6cb481870a17f37efd28f6af4fe230e3ee4f6d7591063c4b6c377cbff63

+# Copyright 1999-2016 Georg Hopp
+# Distributed under the terms of the GNU General Public License v3
+
+EAPI=6
+
+inherit eutils
+
+DESCRIPTION="Event subsystem for the taskrambler framework."
+HOMEPAGE="https://gitlab.weird-web-workers.org/taskrambler/trevent"
+SRC_URI="http://ci-build.weird-web-workers.org/trevent/artifacts/${P}.tar.gz"
+LICENSE="GPL-3+"
+
+SLOT="1.0"
+
+KEYWORDS="amd64 ~x86"
+
+DEPEND="dev-libs/libtrbase:1.0
+	dev-libs/libtrdata:1.0"
+RDEPEND="${DEPEND}"

+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE pkgmetadata SYSTEM "http://www.gentoo.org/dtd/metadata.dtd">
+<pkgmetadata>
+<maintainer type="person">
+	<email>georg@steffers.org</email>
+	<description>Author and primary maintainer</description>
+</maintainer>
+<longdescription>
+	Event system for taskrambler framework.
+</longdescription>
+</pkgmetadata>