build: require cmake 2.8.10 (try_compile with link_libraries support)

Otherwise you will get next errors:
-- Checking whether v8 most of constructors have Isolate* argument, instead of getting current
CMake Error at cmake/Modules/TryCompileFromSource.cmake:10 (try_compile):
  Attempt at a recursive or nested TRY_COMPILE in directory
    /home/travis/build/azat/boostcache
Call Stack (most recent call first):
  CMakeLists.txt:36 (TryCompileFromSource)

Also update travis-ci to install appropriate version of cmake.
This _patch_ tested on ubuntu 12.04 (like travis ci vms) on ec2 and all
works there.

CI: https://travis-ci.org/azat/boostcache/builds/24885358
jsvm: add space between '<' and '::' to compile on more older compilers

jsvm.cpp:56:17: error: ‘<::’ cannot begin a template-argument list [-fpermissive]
jsvm.cpp:56:17: note: ‘<:’ is an alternate spelling for ‘[’. Insert whitespace between ‘<’ and ‘::’
jsvm.cpp:56:17: note: (if you use ‘-fpermissive’ G++ will accept your code)