Your requirements could not be resolved to an installable set of packages. Problem 1 - Conclusion: don't install symfony/http-kernel v2.7.14 (conflict analysis result) - Conclusion: don't install symfony/http-kernel v2.7.19 (conflict analysis result) - Conclusion: don't install symfony/http-kernel v2.7.24 (conflict analysis result) - Conclusion: don't install symfony/http-kernel v2.7.28 (conflict analysis result) - Conclusion: don't install symfony/http-kernel v2.7.35 (conflict analysis result) - Conclusion: don't install symfony/http-kernel v2.7.46 (conflict analysis result) - Conclusion: don't install symfony/http-kernel v2.7.52 (conflict analysis result) - Conclusion: don't install symfony/http-kernel v2.8.7 (conflict analysis result) - Conclusion: don't install symfony/http-kernel v2.8.12 (conflict analysis result) - Conclusion: don't install symfony/http-kernel v2.8.17 (conflict analysis result) - Conclusion: don't install symfony/http-kernel v2.8.21 (conflict analysis result) - Conclusion: don't install symfony/http-kernel v2.8.28 (conflict analysis result) - Conclusion: don't install symfony/http-kernel v2.8.39 (conflict analysis result) - Conclusion: don't install symfony/http-kernel v2.8.51 (conflict analysis result) - Conclusion: don't install symfony/http-kernel v2.8.52 (conflict analysis result) - Conclusion: don't install symfony/http-kernel v3.0.9 (conflict analysis result) - Conclusion: don't install symfony/http-kernel v3.1.1 (conflict analysis result) - Conclusion: don't install symfony/http-kernel v3.1.5 (conflict analysis result) - Conclusion: don't install symfony/http-kernel v3.1.10 (conflict analysis result) - Conclusion: don't install symfony/http-kernel v3.2.9 (conflict analysis result) - Conclusion: don't install symfony/http-kernel v3.2.14 (conflict analysis result) - Conclusion: don't install symfony/http-kernel v3.3.0 (conflict analysis result) - Conclusion: don't install symfony/http-kernel v3.3.6 (conflict analysis result) - Conclusion: don't install symfony/http-kernel v3.3.10 (conflict analysis result) - Conclusion: don't install symfony/http-kernel v3.3.18 (conflict analysis result) - Conclusion: don't install symfony/http-kernel v3.4.3 (conflict analysis result) - Conclusion: don't install symfony/http-kernel v3.4.4 (conflict analysis result) - Conclusion: don't install symfony/http-kernel v3.4.9 (conflict analysis result) - Conclusion: don't install symfony/http-kernel v3.4.11 (conflict analysis result) - Conclusion: don't install symfony/http-kernel v3.4.13 (conflict analysis result) - Conclusion: don't install symfony/http-kernel v3.4.21 (conflict analysis result) - Conclusion: don't install symfony/http-kernel v3.4.34 (conflict analysis result) - Conclusion: don't install symfony/http-kernel v3.4.49 (conflict analysis result) - Conclusion: don't install symfony/http-kernel v4.0.3 (conflict analysis result) - Conclusion: don't install symfony/http-kernel v4.0.4 (conflict analysis result) - Conclusion: don't install symfony/http-kernel v4.0.9 (conflict analysis result) - Conclusion: don't install symfony/http-kernel v4.0.11 (conflict analysis result) - Conclusion: don't install symfony/http-kernel v4.0.13 (conflict analysis result) - Conclusion: don't install symfony/http-kernel v4.0.15 (conflict analysis result) - Conclusion: don't install symfony/http-kernel v4.1.0 (conflict analysis result) - Conclusion: don't install symfony/http-kernel v4.1.13 (conflict analysis result) - Conclusion: don't install symfony/http-kernel v4.2.0 (conflict analysis result) - Conclusion: don't install symfony/http-kernel v4.2.11 (conflict analysis result) - Conclusion: don't install symfony/http-kernel v4.2.12 (conflict analysis result) - Conclusion: don't install symfony/http-kernel v4.3.11 (conflict analysis result) - Conclusion: don't install symfony/http-kernel v4.4.8 (conflict analysis result) - Conclusion: don'